Inorganic ChemistryDr.RiteshPandey Qualitative Analysis 1. INTRODUCTION : Qualitative analysis involves identification of ions (cations and anions) of a salt or a mixture of salts through their characteristic reactions. The process involves:(i) Analysis of anions and (ii) Analysis of cations 1.1 Physical Examination of Compounds by Heating Effects : Heating effect of carbonate & bicarbonate salts All carbonates except (Na, K, Rb, Cs) decompose on heating giving CO 2 Li 2CO3 Li 2O CO2 MCO 3 MO CO2 M Be, Mg , Ca, Sr , Ba 1 Ag 2CO3 2 Ag CO2 O2 2 Black Yellow Cu(OH)2 . CuCO3 2 CuO CO2 H2O Basic Cu (II) carbonate ZnCO 3 ZnO Yellow (hot white (cold) CO2 450 C PbCO3 PbO CO2 2 PbCO3 . Pb (OH)2 Pb3O 4 CO CO2 H2O 1 HgCO3 Hg O2 CO2 2 (NH4 )2 CO3 2NH3 H2O CO2 All bicarbonates decompose to give carbonates and CO 2 . eg. 2NaHCO 3 Na 2CO3 CO2 H2O 2 [General reaction 2 HCO 3 CO3 H2O CO2 ] Heating effect of ammonium salts (NH4 )2 Cr2O7 N2 Cr2O3 4 H2O NH4NO 2 N2 2H2O NH4NO 3 N2O 2H2O 2 NH 4 ClO 4 N2 Cl2 2 O 2 4 H2 O 2NH4 IO3 N2 I 2 O2 4 H2O [If anionic part is oxidising in nature, then N2 will be the product (some times N 2 O ) ] (NH4 )2 HPO 4 HPO3 H2O 2NH3 (NH4 )2 SO4 2NH3 H2SO4 2 (NH4 )3 PO4 6 NH3 P2O5 3 H2O (NH4 )2 CO3 2NH3 H2O CO2 [If anionic part is weakly oxidising or non oxidising in nature then NH 3 will be the product.] Heating effect of nitrate salts Ritesh Classes Education should aim minds but reach hearts 2 9007102353/9831813135 MNO 3 MNO 2 [M Na , K , Rb , Cs] 1 O2 2 2 LiNO 3 Li 2O 2 NO 2 1 O2 2 2M(NO 3 )2 2MO 4 NO 2 O2 [M all bivalent metals eg. Zn 2 , Mg 2 , Sr 2 , Ca 2 , Ba 2 , Cu 2 , Pb 2 ] Hg (NO 3 ) 2 Hg 2 NO 2 O 2 2 AgNO 3 2 Ag 2 NO 2 O 2 ; Heating effect of Halides salts 2 FeCl3 2 FeCl 2 Cl2 ; AuCl 3 AuCl Cl2 Hg2Cl2 HgCl 2 Hg NH4Cl NH3 HCl ; Pb(SCN)4 Pb (SCN)2 (SCN)2 PbCl4 PbCl2 Cl2 [PbBr2 PbBr2 Br2 & PbI 4 does not exists] Heating effect of hydrated chloride salts MgCl 2 . 6 H2O MgO 2HCl 5 H2O 2FeCl3 . 6 H2O Fe2O3 6 HCl 9 H2O 2 AlCl 3 . 6 H2O Al 2O 3 6 HCl 9 H2O 50 C 58 C 140 C CoCl2 . 6 H2O CoCl2 . 4 H2 O CoCl2 . 2 H2O CoCl2 2 H2O Pink 2 H2O Pink 2 H2O Red violet Blue Heating effect of hydrated Sulphate salts 100 C 220 C 800 C CuSO 4 . 5 H2 O CuSO 4 . H2O CuSO 4 CuO SO 2 4 H2O Blue vitriol H2O Bluish White White 1 O2 2 750 C 300 C CuO SO3 Black FeSO 4 . 7 H2O FeSO 4 Fe 2O3 SO 2 SO3 (very important) 7 H2 O Green Vitriol Fe2 (SO4 )3 Fe2O3 3 SO3 MgSO 4 . 7 H2O MgSO 4 [Same as ZnSO 4 ] 7 H2O 1 1 120 C CaSO 4 . 2 H2 O CaSO 4 H2 O 1 H2 O 2 2 Gypsum CaSO4 . 2 H2 Plaster of pairs 1 1 H2O 2 O 220 C 1 H2O Dead burnt 2 CaSO4 Na 2S2O3 . 5 H2O Na 2S2O3 5 H2O 3 Na 2SO4 Na 2S5 (From 4 moles) Ritesh Classes Education should aim minds but reach hearts 3 9007102353/9831813135 70 C 70 200 C 200 C ZnSO 4 . 7 H2O ZnSO 4 . 6 H2O ZnSO 4 . H2O ZnSO 4 800 C ZnO SO2 Na 2SO3 SO2 2NaHSO 4 Na 2S2O5 H2O Na 2S Na 2SO4 1 O2 2 2NaHSO 4 Na 2SO4 H2O SO3 Heating effect of Oxide salts 2 Ag 2 O 4 Ag O 2 300 C PbO 2 PbO yellow 400 C 1 O2 2 ; HgO HgO Hg ; red strong heating 1 O2 2 6 PbO O 2 Pb3 O 4 Re d lead Litharge 900 C 3 MnO 2 Mn 3O 4 O2 ; 7 2 CrO5 Cr2O3 O2 2 ; ZnO ZnO White Yellow PbO PbO Yellow Re d (Massicot) 420 C 2 CrO3 Cr2O3 3 O2 2 (Litharge) 5 I 2O5 I 2 O2 2 ; Heating effect of dichromate & chromate salts (NH4 )2 Cr2O7 N2 Cr2O3 4 H2O 7 2 K 2Cr2O7 2 K 2CrO4 Cr2O3 O2 2 Heating effect of phosphate salts NaH 2PO 4 1 phosphate salt Na 3PO 4 3 phosphate salt H2O NaPO 3 Na 2HPO 4 2 phosphate salt H2O Na 2P2O7 No effect High temp. Na (NH 4 )HPO 4 . 4 H2O NaNH 4 HPO 4 NaPO 3 NH3 H2O 4 H2O 2 Mg (NH4 ) PO4 Mg 2P2O7 2NH3 H2O Heating effect of Acids 1 2 HNO 3 H2O 2 NO 2 O2 2 444 C H2SO4 H2O SO3 800 C H2SO4 H2O SO2 1 O2 2 Ritesh Classes Education should aim minds but reach hearts 4 9007102353/9831813135 H2 SO 3 2 H2 SO 4 S H2 O 3 HNO 2 HNO 3 2 NO H2 O HClO 3 HClO 4 ClO 2 H2 O 3 HOCl 2 HCl HClO 3 Undergoes disproportionation reaction 4 H3PO 3 3 H3 PO 4 PH3 200 C 2 H3PO 2 H3PO 4 PH3 2 NaH 2PO 2 Na 2HPO 4 PH3 220 C 320 C 320 C H3PO 4 H4P2 O 7 4 HPO 3 2 P2O 5 2 H2O 100 C 140 C Re d H3BO3 4 HBO 2 H2B 4 O7 2 B 2O3 H2O hot H2 C 2 O 4 H2 O CO CO2 Heating effects of acetate, formate, oxalate salts CH3CO2K K 2CO3 CH3COCH3 Pb (OAc )2 PbO CO2 CH3COCH3 Mg (OAc )2 MgO CO2 CH3COCH3 Be (OAc )2 BeO CO2 CH3COCH3 Ca(OAc )2 CaCO3 CH3COCH3 Ba (OAc )2 BaCO3 CH3COCH3 350 C HCO2Na Na 2C2O4 H2 2HCOOAg HCOOH 2Ag CO2 (HCOO)2 Hg HCOOH Hg CO2 Na 2C2O4 Na 2CO3 CO FeC 2O 4 FeO CO CO2 SnC2O4 SnO CO2 CO Ag 2C2O4 2 Ag 2 CO2 HgC 2O4 Hg 2 CO2 PART – A (Objective type) 1. When a reagent (A) react with Fe3 the solution turns red due to the formation of a compound (B). The reagent causes no change in colour when it reacts with Fe2 in the pure state. (A) and (B) are respectively (A) K 4 Fe(CN)6 and Fe 4 Fe (CN)6 3 (B) NH 4 SCN and [Fe (SCN )3 ] (C) K 3 Fe (CN)6 and K 2Fe Fe (CN)6 (D) Na 2HPO 4 and FePO 4 2. A solution is 10 3 M each in Mn 2 , Fe 2 , Zn 2 and Hg 2 . It is treated with H2 S in alkaline medium. If Ksp of MnS, FeS and HgS are 10 15 , 10 20 and 10 54 respectively, which one will precipitate first? (A) FeS (B) MgS (C) HgS (D) ZnS 3. A mixture of zinc oxide and cupric oxide can be separated by (A) boiling the mixture with caustic potash solution and filtering Ritesh Classes Education should aim minds but reach hearts 5 9007102353/9831813135 (B) boiling the mixture with dilute HNO 3 and filtering (C) heating with carbon (D) removing cupric oxide with magnet 4. The effective component of bleaching powder is (A) Ca2 (C) (OCl) 22 (B) Cl (D) OCl 5. A sodium salt of an unknown anion when treated with MgCl 2 gives a white precipitate, only on boiling. The anion is (A) CO 32 (B) HCO 3 (C) NO 3 (D) SO 24 6. [ X] H2SO4 [ Y] a colourless gas with suffocating smell [ Y] K 2Cr2O7 H2SO4 green solution [X] and [Y] is (A) SO32 , SO 2 (B) Cl , HCl (C) S 2 , H2 S (D) CO32 , CO2 7. When the solution of an inorganic salt in sodium hydroxide to boiled, a pungent gas is produced, which turns moist red litmus paper blue and a mercurous nitrate solution black. This indicates the presence of ___________ ion in the salt. 2 (A) CO 3 (B) NH 4 (C) Sn 4 (D) NO 2 8. The constituents of which of the following pairs of ions in a dilute HCl medium cannot be separated by passing H2 S gas through it? (A) Ca2 and Hg 22 (B) Cu 2 and Cd 2 (C) Zn 2 and Sn 2 (D) Co 3 and Cu 2 9. Highly pure dilute solution of sodium in liquid ammonia (A) Shows blue colour (B) exhibits no electrical conductivity (C) produces sodamide (D) produces hydrogen gas 10. Heating (NH 4 ) 2 Cr2 O 7 yields a gas , which is also obtained by (A) Mg 3N2 in H2O (B) heating NH 4NO 2 (C) heating NH 4NO 3 (D) Na 2O 2 in H2O PART – B (Short Subjective) 1. Identify (A), (B), (C) … (H) in the following and explain reactions. (A) black + dil H2SO4 B (aq) C (aq) D (g) (B) KI brown cloured solution hypo white ppt (E) H colourless solution (C) (C) K 3 Fe (CN)6 blue (F) (D) (CH3 COO )2 Pb black (G) (B) or (C) BaCl 2 white ppt (H) MnO 4 Ritesh Classes Education should aim minds but reach hearts 6 9007102353/9831813135 (B) (D) black ppt (I) 2. (A) is yellow coloured solid partially soluble in aqueous NH 3 . (A) is soluble in Na 2 S 2 O 3 (hypo) solution forming a complex (B) which on heating is converted into (C) (black). (C) is converted into white ppt (D) on reaction with HCl and HNO 3 . (D) is soluble in aqueous NH 3 forming (E). Identify (A), (B), (C), (D) and (E) and explain reactions. 3. Hydrate salt ( A ) BaCl 2 white (B) insoluble in HNO 3 . ( A ) (in dil HCl ) H2S black ppt soluble in 50% HNO 3 ( A ) aq NH 3 (excess ) deep blue solution (C) ( A ) microcosmic salt green (D) when hot ( A ) K I solution reddish brown changing to white ppt after hypo is added 2.495 g of (A) gave 2.33 g of (B). Identify (A), (B), (C) and (D) and explain reactions. 4. ( A ) (black ) dil H2SO 4 (B) (aq) (C) (gas ) (C) (CH 3 COO )2 Pb black (B) NaOH green ppt (D) changing to brown (E) by atmospheric O 2 (B) K 3 Fe (CN) 6 blue (F) (E) HCl deep yellow coloured solution (G) . (F) KCNS red coloured solution (H). what are (A) to (H) and explain reactions. 5. Black coloured (insoluble in H2O ) solid (A) does not dissolve in dil. HNO 3 . Aqua regia can dissolve (A) forming (B). (B) gives yellow ppt (C) with NaOH. (B) also gives orange ppt (D) with KI ; (D) dissolves in excess of KI forming (E). (E) gives brown ppt with NH 4 salt in presence of NaOH. (A) is precipitated if H2 S gas is passed into solution of (B) in dil HCl. Identify (A) to (E) and explain reactions. 6. Identify (A) and (B) in the following and explain reactions given V.D. of (A) is 17. A decolorises acidified KmNO 3 . (A) also gives brown ppt (B) with alkaline KMnO 4 . (A) also liberates I 2 from acidifies KI solution. (A) also removes back stains from old oil paintings. 7. ( A ) tap water white turbidity soluble in aq NH 3 ( A ) residue (B) + (C) (oxides of N) O 2 aqueous (A) give brown ring on adding FeSO 4 and conc H 2 SO 4 . (C) is paramagnetic and forms dimer of V.D. 46. Identify (A), (B) and (C) and explain reactions. 8. (A) is hydrated salt. 2.48 g of (A) on heating gives 1.58 g of anhydrous salt (B). (i) Aq (A) AgNO 3 white turbidity changing to black. (ii) Aq (A) decolorises I 2 in KI (iii) Aq (A) +dil HCl white turbidity (iv) Aq (A) dissolves unreacted AgBr of photographic plate. Identify (A) and explain reactions. 9. (A), an important laboratory reagent, turns red litmus blue, imparts golden yellow colour in flame and is a good precipitating agent. (A) reacts with Zn or Al forming H2 gas. (A) gives white ppt with ZnCl 2 or AlCl 3 but ppt dissolves in excess of (A). What is (A) and explain reactions. Ritesh Classes Education should aim minds but reach hearts 7 9007102353/9831813135 10. Identify (A) and (B) based on following reactions : NaOH HCl (B) (g) white fumes (i) ( A ) (ii) after (B) is expelled completely, resultant alkaline solution again gives gas (B) on heating with zinc. (iii) ( A) N2O H2O 11. Identify (A), (B), (C) and (D) based on following observations: (i) ( A ) glassy transparent bead (B) on platinum wire. (B) CuSO 4 coloured bead (C) ignite (ii) ( A) conc H2SO4 CH3CH2OH green flame (D) (iii) Aqueous solution of (A) is alkaline 12. Identify (A) to (C) in the following : A (aq) KI I 2 A (aq) CO 2 milky (B) A (aq) (paste) CH3 CH2OH product (C) (an anaesthetic) 13. Aqueous solution of (A) is deep yellow but (A) (solid) is brown. (A) in aqueous solution gives white ppt with AgNO 3 soluble in NH 3 Yellow solution of (A) changes to green solution (B) on passing H2 S . (A) is precipitated as brown ppt (C) on adding NH 4 OH in presence of NH 4 Cl Precipitate (C) is insoluble in NaOH even in presence of oxidising agents but (C) dissolves in HCl forming (A) again. Aqueous (A) gives blue coloration (D) with K 4 Fe (CN) 6 . Aqueous (B) also gives blue coloration (E) with K 3 Fe (CN)6 . Identify (A) to (E) and explain difference between (D) and (E). 14. Identify inorganic salt (A) which in hydrated and light green in colour and gives following reactions. (i) (A) decolorises acidified MnO 4 and turns acidified Cr2O7 2 green. (ii) (A) in aq solution gives light green turbidity which dissolves in dil acid. (iii) (A) gives white ppt with BaCl 3 solution insoluble in conc HCl 2.78 g of (A) gave 2.33 g of white ppt (iv) ( A ) (B) (blackish brown) (C) (D) oxides of sulphur oxidation (C) (D) (C) turns acidified K 2 Cr2 O 7 solution green (B) HCl (E) deep yellow (E) KCNS red colour 15. Identify (A), (B), (C) and (D) based on following observations : (i) MaOH K Hgl 4 B (g) 2 brown ppt (A) light green coloured hydrated salt K Fe (CN) 6 (ii) ( A ) 3 blue ppt (C) Ritesh Classes Education should aim minds but reach hearts 8 9007102353/9831813135 BaCl 2 (iii) ( A ) white ppt (D) conc HCl (iv) 3.92 g of (A) required 100 mL of 0.02 M MnO 4 in acidic medium. 16. A colourless mixture of two salts (A) and (B) (excess) is soluble in H2O . (A) turns blue litmus red and (B) turns red litmus blue. (A) gives white ppt with (B), which dissolves in excess of (B) forming (C). (A) when placed in atmosphere gives fumes and can form dimmer. (A) gives white ppt with NH 4 Cl and NH 4 OH soluble in (B). Identify (A), (B) and (C) and explain reactions. 17. Identify (A) based on following facts : (a) (A) reduces HgCl 2 solution to white ppt changing to grey. (b) A turns FeCl 3 yellow coloured solution to green. (c) (A) gives white ppt with NaOH woluble in excess of NaOH. (d) (A) gives yellow dirty ppt on passing H2 S gas, soluble in yellow ammonium sulphide (YAS). (e) (A) gives chromyl chloride test. 18. You have a mixture of CO 2 , SO 2 and O 2 gas. You have been provided following reagents for testing (A) lime water (B) acidified potassium dichromate solution (C) pyrogallol Arrange these reagents in order such that only one gas is tested at one time. 19. Identify gas (X) based on following facts: (A) (X) occupies 0.35 L per g at NTP (B) (X) turns acidified K 2 Cr2 O 7 solution green. (C) (X) decolorizes acidified KMnO 4 solution. (D) (X) gives white turbidity when H2 S gas is passed into its aqueous solution. 20. (A) is scarlet (reddish-orange) inorganic salt insoluble in H2O . (A) on reaction with HNO 3 gives blackish-brown residue (B) and colourless solution of (C). (C) gives yellow ppt with KI solution as well as with K 2CrO 4 . (C) also gives black ppt (D) with H2 S in HCl solution; ppt (D) dissolves in dil HNO 3 . (B) on heating with conc. HNO 3 and Mn (NO 3 )2 forms pink coloured solution (E). Identify (A), (B), (C), (D) and (E). 21. (A) is a ternary salt with divalent cation. (A) gives yellow ppt with K 2CrO 4 as well as with AgNO 3 . (A) give apple green colour in flame. (A) is precipitated by H2 S neither in acidic nor ammonical medium, but addition of (NH 4 ) 2 CO 3 in NH 4 OH gave white ppt (B). 0.297 g of (A) gave 0.197 g of (B). Identify (A) and explain reactions. 22. Chromite ore (A) (FeCr 2 O 4 ) is fused with NaOH in presence of H2O 2 when yellow coloured solution (B) and residue (C) are obtained. (C) is separated by filtration and dissolved in conc HCl forming a yellow coloured solution (D). (D) gives red colour with NH 4 CNS and blue colour with K 4 Fe (CN)6 . (D) changes to green (E) when Zn is added into it, however, H2 gas if passed into (D) has no effect, (B) changes to orange (F) on reaction with dil H 2 SO 4 and again (F) changes to (B) on adding NaOH. (F) on reaction with NH 4 Cl and subsequent heating gives G (green) and H (gas). Identify (B) to (H) and explain reactions. Ritesh Classes Education should aim minds but reach hearts 9 9007102353/9831813135 23. A colourless salt (A), soluble in water, gives a mixture of three gases (B), (C) and (D) along with water vapours. (B) is blue, (C) is red and gas (D) is neutral towards litmus paper. Gas (B) is also obtained when (A) is heated with NaOH and gives brown ppt with K 2Hgl 4 . Solution thus obtained gives white ppt (E) with CaCl 2 solution in presence of CH 3 COOH . (E) decolorises MnO 4 / H . Gas (C) turns lime water milky and gas (D) burns with a blue flame. Identify (A) to (D) and explain reactions. 24. Colourless salt, (A) (insoluble in water) + dil H2 SO 4 (B) C (g) NaOH NaOH (B) (D) ( white ppt ) (E) (soluble) excess NH 4 Cl NH 4 OH (C) (C) no ppt ( A ) ( A ) ( white ppt ) (C) (F) ( yellow coloured solution) light green (G) K Fe (CN) 6 4 blue (H) AgNO 3 White ppt (I) (soluble in NH3 ) (C) H2O (J) colloidal white turbidity Cr O2 / H 27 green Ca (OH) 2 milky Identify (A) to (J) and explain reactions. 25. An aqueous solution of salt A gives a white crystalline precipitate B with NaCl solution. The filtrate gives a black precipitate C when H2 S is passed through it. Compound B dissolves in hot water and the solution gives yellow precipitate D on treatment with potassium iodide and cooling. The compound A does not give any gas with dilute HCl but liberates a reddish brown gas on heating. Identify the compounds A to D giving the involved equations. 26. A white amorphous powder A when heated gives a colourless gas B, which turns lime water milky and the residue C which is yellow when hot but white when cold. The residue C dissolves in dilute HCl and the resulting solution gives a white precipitate on addition of potassium ferrocyanide solution. A dissolves in dilute HCl with the evolution of a gas which is identical in all respects with B. The solution of A as obtained above gives a white precipitate D on addition of excess of NH 4 OH and on passing H2 S . Another portion of this solution gives initially a white precipitate E on addition of NaOH solution, which dissolves on further addition of the base. Identify the compounds A to E. 27. Compound A is a light green crystalline solid. It gives the following tests. (i) It dissolves in dilute sulphuric acid. No gas is produced. (ii) A drop of KMnO 4 is added to the above solution. The pink colour disappears. Ritesh Classes Education should aim minds but reach hearts 10 9007102353/9831813135 (iii) Compound A is heated strongly. Gases B and C with pungent smell came out. A brown residue D is left behind. (iv) The gas mixture (B and C) is passed into a dichromate solution. The solution turns green. (v) The green solution from step (iv) gives a white precipitate E with a solution of barium nitrate. (vi) Residue D from (v) is heated on charcoal in reducing flame. It gives a magnetic substance. Identify the compounds A to E. 28. An unknown solid mixture contains one or two of the following. CaCO 3 , BaCl 2 , AgNO 3 , ZnSO 4 and NaOH . The mixture is completely soluble in water and the solution gives pink colour with phenolphthalein. When hydrochloric acid is gradually added to the above solution, a precipitate is formed which dissolves with further addition of the acid. What components is/are present in the solid? Give involved chemical equations. 29. A mixture of two salts was treated as follows. (i) The mixture was heated with MnO 2 and concentrated H 2 SO 4 when yellow-green gas was liberated. (ii) The mixture on heating with NaOH solution gave a gas which turned red litmus blue. (iii) Its solution in water gave blue recipitate with potassium ferrocyanide and red colouration with ammonium thiocyanate. (iv) The mixture was boiled with potassium hydroxide and the liberated gas was bubbled through an alkaline solution of K 2Hg I 4 to give brown precipitate. Identify the two salts. Give ionic equations for the reactions involved. 30. Match the following using three columns with (X) containing radicals, (Y) the reagents used and (Z) the compound formed when (X) and (Y) react. (X) (Y) (Z) 2 (I) Fe (a) NH 4 SCN (A) Cherry red ppt Fe3 (III) Ni 2 (b) (IV) Co2 (d) K 3 Fe (CN)6 (II) (c) (B) Turnbull’s blue DMG K 4 Fe (CN)6 (C) Prussian blue (D) Blue 31. (a) If CO 2 (g) under pressure is passed into Na 2CrO 4 (aq), Na 2Cr2O 7 (aq) is formed. What is the function of the CO 2 (g) ? (b) When Zn is added to acidic solution of Na 2 Cr2 O 7 , the colour of the solution changes from orange to green then to blue, and, over a period of time, back to green. Explain. 32. A solution may contain any of the following ions : Fe 3 , Ni 2 , Cr 3 , Zn 2 , Mn 2 . Based on the following experiment and results there in, indicate which of the ions would be present? Indicate any wrong information, if any. (A) The original solution is treated with (NH 4 ) 2 S (a substitute of H2 S ) in a buffered basic solution. A dark precipitate is obtained. (B) The ppt for (A) dissolves in aqua regia. (C) The filtrate after separating ppt in (A) is treated with NaOH and H2O 2 , A dark ppt is separated. Filtrate is colourless. (D) The ppt from (C) dissolves in HCl (aq) giving a coloured solution. (E) The solution from (D) is treated with aqueous NH 3 . A dark ppt forms. Ritesh Classes Education should aim minds but reach hearts 11 9007102353/9831813135 (F) The ppt from (E) is soluble in HCl (aq) and solution develops an intense red colour when treated with SCN (aq) 33. Identify (A) to (O) in the following. (A) (hydrated bluish brown coloured double salt) gives white ppt (B) with BaCl 2 insoluble in conc. HCl. 0.9915 g of (A) gave 0.932 g of white ppt H2 S ( A ) (in dil HCl) black ppt (C) (insoluble in yellow ammonium sulphide) aq NH 3 blue ppt (E) blue coloured solution (D) excess aq NH 3 deep blue solution (F) HNO 3 NH 4 SCN KI white ppt (G) black ppt (H) (appeared after adding hypo ) Filtrate after separating (C) light green coloured solution (L) blue (M) K 3 Fe (CN)6 NH 4Cl NH 4OH yellow coloured solution (J) gas (K ) K 4 Fe (CN)6 blue (O) brown ppt ( I) HCl SnCl 2 Green (L ) NH 4SCN intense red (N) (Cu = 63.5, Fe = 56, So 4 2 96 , H2O 18 , Ba2 137 ) 34. Colourless salt (A), on heating with NaOH, gave gas (B) that can also be obtained when Mg 3N2 reacts with H2O . When reaction of (A) with NaOH was complete, solution obtained on reaction with FeSO 4 and conc. H 2 SO 4 gave a brown coloured ring (C) between two layers. Identify (A) to (F) and explain reactions. 35. Identify (A) to (G) in the following scheme and name the process. CaCO3 ( A) (B) gas ( A ) H 2 O ( C) (C) (B) CaCO 3 H2O (D) (C) (E) gas (E) H2O (B) (F) NaCl (F) (G) (D) (G) Na 2CO3 H2O (B) Ritesh Classes Education should aim minds but reach hearts 12 9007102353/9831813135 36. A hydrated metallic salt A, light green in colour, gives a white anhydrous residue B after being heated gradually. B is soluble in water and its aqueous solution reacts with NO to give a dark brown compound C. B on strong heating gives a brown residue and a mixture of two gases E and F. The gaseous mixture, when passed through acidified permanganate, discharge the pink colour and when passed through acidified BaCl 2 solution, gives a white precipitate. Identify A, B, C, D, E and F. 37. The gas liberated, on heating a mixture of two salts with NaOH, gives a reddish brown precipitate with an alkaline solution of K 2HgI 4 . The aqueous solution of the mixture on treatment with BaCl 2 gives a white precipitate which is sparingly soluble in concentrated HCl. On heating the mixture with K 2 Cr2 O 7 and concentrated H 2 SO 4 , red vapours A are produced. The aqueous solution of the mixture gives a deep blue colouration B with potassium ferricy anide solution. Identify the ions in the given mixture and write the balanced chemical equation for the formation of A and B. 38. A light bluish green crystalline compound responds to the following tests. (i) Its aqueous solution gives a brown precipitate or colouration with alkaline K 2 [HgI 4 ] solution. (ii) Its aqueous solution gives a blue colour with K 3 [Fe(CN)6 ] solution. (iii) Its solution in hydrochloride acid gives a white precipitate with BaCl 2 solution. Identify the ions present and suggest the formula of the compound. 39. A is a binary compound of a univalent metal. 1.422 g of A reacts completely with 0.321 g of sulphur in an evacuated and sealed tube to give 1.743 g of a white crystalline solid B that forms a hydrated double salt, C with Al 2 (SO 4 )3 . Identify A, B and C. 40. A certain inorganic compound A on heating loses its water of crystallization. On further heating, a blacksish brown powder B and two oxides of sulphur, C and D, are obtained. The powder B on boiling with hydrochloric acid gives a yellow solution E. When H2 S is passed in E a white turbidity F and an apple green solution G are obtained. The solution E on treatment with thiocyanate ions gives a blood-red coloured compound H. Identify the compounds from A to H. 41. An unknown inorganic compound X loses its water of crystallization on heating and its aqueous solution gives the following reactions. (a) It gives a white turbidity with dilute hydrochloric acid solution. (b) It decolourises a solution of iodine in potassium iodide. (c) It gives a white precipitate with silver nitrate solution which turns black on standing Identify the compound X giving chemical equations for the steps (a) to (c). 42. A black coloured compound A on reaction with dilute H 2 SO 4 gives a gas B which on passing in a solution of an acid C gives a white turbidity D. Gas B when passed through an acidified solution of a compound E gives precipitate F which is soluble in dilute nitric acid. After boiling this solution, an excess of NH 4 OH is added, a blue coloured compound G is formed. To this solution, on addition of acetic acid and aqueous potassium ferrocyanide, a chocolate precipitate H is obtained. On addition of an aqueous solution of barium chloride to an aqueous solution of E a white precipitate insoluble in HNO 3 is obtained. Identify the compounds from A to H. 43. An aqueous solution of an unknown compound X gives the following reactions. (a) It gives brown colour with alkaline KMnO 4 solution. (b) It forms HCl and evolves O 2 when reacted with Cl 2 gas Ritesh Classes Education should aim minds but reach hearts 13 9007102353/9831813135 (c) It gives orange-yellow colour with acidified titanic sulphate solution. Identify X giving the equations involved in steps (a) and (b). 44. An inorganic compound X gives a brick red flame on performing flame test. This compound also gives the following observations. (i) Smells of chlorine when placed in moist air. (ii) The addition of KI and CH 3 COOH to the suspension of X gives a brown colour. (iii) With an aqueous solution of potassium ferrocyanide a chocolate colored precipitate is obtained. 45. A certain metal A is boiled in dilute nitric acid to give a salt B an oxide of nitrogen, C. An aqueous solution of B with brine gives a precipitate D which is soluble in ammonium hydroxide. On adding aqueous solution of B to hypo solution, a white precipitate E is obtained. E on standing turns to black compound F. Identify the compounds A to F. 46. When a substance (A) was treated with dil HCl, a colourless gas (B) was evolved, which turned moist litmus paper red. On budding (B) through lime water, a precipitate (C) was formed, but passage of further gas resulted in a clear solution (D). A small sample of (A) was moistened with conc. HCl and placed on a platinum wire, and introduced into a Bunsen burner flame where if causes a green flame coloration. On strong heating, (A) decomposed, giving a white solid (E) which turned red litmus paper blue. 1.9735 g of (A) was heated strongly and gave 1.5334 g of (E). The sample (E) was dissolved in water and made upto mL in a standard flask. 25 mL aliquots were titrated with acid and required 20.30 mL of 0.0985 M HCl.. Name the compounds (A) to (E), and give equations for all the reactions. Calculate the gram molecular weight of (A). 47. Substance (A) is a yellowish white deliquiescent solid which sublimes and has a vapour density of 133.5 (w.r.t. H = 1). (A) reacted violently with water forming solution (B) which turns blue litmus red. A sample of (B) gave a curdy yellowish precipitate (C) on addition of dilute HNO 3 and AgNO 3 solution, but this partially dissolves an addition of dilute NH 4 OH , though a gelatinuous white ppt (D) was formed in place, (D) was filtered off and dissolved in excess of NaOH, forming a clear solution (E). When CO 2 was passed into (E), compound (D) was precipitated. Substance (A) dissolved unchanged in dry ether, and when this solution was treated with LiH, one of the two products (F) or (G) was formed, depending on whether the LiH was excess or not. Qualitative analysis of solution(B) gave a white gelationsous precipitate in group III. When 0.2670 g of (A) was dissolved in water and treated with 8-hydroxy quinoline (X), 0.4594 g or precipitate (Y) was formed. Identify (A) to (G) and explain reactions. 48. Write a balanced net ionic equation for each of the following reactions : 2 (a) A CrO 4 solution turns from yellow to orange upon addition of acid. (b) Fe 3 (aq) reacts with KSCN (aq) to give deep red solution. (c) Copper metal reacts with nitric acid to give NO gas and a blue solution. Ritesh Classes Education should aim minds but reach hearts 14 9007102353/9831813135 (d) A deep green solution of Cr (OH)3 in excess base turns yellow on addition of hydrogen peroxide. 49. A light coloured crystalline solid A has 27.55% H2O . A gives following reactions : BaCl solution I : A 2 white ppt (B) insoluble in conc HNO 3 . K [Fe(CN) ] solution II : A 3 6 a dark-blue ppt (C) K HgI / NaOH solution 4 brown ppt (D) III : A 2 Identify A. 50. Identify colourless salt (A) based on the following reactions : NaOH Aqueous solution of ( A ) white ppt soluble in excess of NaOH (B) H2SO 4 H2 O 2 white ppt soluble in CH 3 COONH 4 (D) black ppt (C) AgNO 3 Aqueous solution of (A) white ppt soluble is aqueous NH 3 (E) K CrO 4 2 yellow ppt (F) HCl, H2S black ppt (G) insoluble in NaOH EXERCISE – I SECTION – A (Single Option Correct) : 51. Yellow coloured solution of FeCl 3 changes to light green when : (A) SnCl 2 is added (B) Zn is added (C) H2 S gas is passed 52. Turnbull’s blue and Prussian’s blue respectively are : FeII FeII (CN)6 I (A) I, II 2 FeII FeII (CN) 6 II (B) I, II Ritesh Classes Education should aim minds but reach hearts FeII FeIII (CN)6 III (C) III, IV 15 (D) all true FeIII FeII (CN)6 IV (D) IV, III 9007102353/9831813135 53. Fe (OH)3 and Cr (OH)3 ppt are separated by : (A) Aq. NH 3 (B) HCl (C) NaOH / H2O 2 (D) H 2 SO 4 54. Fe2 does not give blue colour with K 4 Fe (CN)6 but on its reaction with (X), blue colour appears. (X) can be (A) MnO 4 / H (B) H 2 SO 4 (C) NH 3 55. Which of the following are soluble in excess of NaOH ( X) : As 2 S 3 ; ( Y ) : CuS ; ( Z) AlCl 3 : (A) X, Y, Z (B) Y, Z (C) X, Z (D) HCl (D) X, Y 56. A mixture on heating gave a gas used as an anaesthetic, 1.1 g of gas occupies 0.56 L at NTP. Mixture contains: (A) NaNO 3 NH 4 Cl (B) NaNO 2 NH 4 Cl (C) CaCO 3 MgCO 3 (D) NH 4 Cl Na 2 SO 4 57. Ferric alum gives red colour with NH 4 SCN due to formation of : (A) Al (SCN )3 (B) Fe (SCN)3 (D) [Fe (SCN ) 2 (C) Fe (SCN )3 Cu2 , 58. Colourless salt ( X) ( Y) coloured bead (Z), (X) can be : (A) borax (B) microcosmic salt (C) both (A) and (B) (D) none of these 59. Cr2O7 2 CrO4 2 . This change is based on change orange green in P H . Probable values of x and y can be : (A) 8, 6 (B) 8, 10 (C) 4, 6 (D) Change is independent of P H 60. K 2 Cr2 O 7 conc H2SO 4 H2 O 2 + ether blue perchromic anhydride (in ethereal layer). Blue colour is due to : (A) CrO 3 (B) H2CrO 4 (C) H2 Cr2 O 3 (D) CrO 5 61. H2 S would seprate the following at pH < 7 : (A) Zn 2 , Co2 (B) Cu 2 , Cd 2 (C) Cu 2 , Cr 3 62. Solution of (X) in dil HCl + H2 O white turbidity : (D) Cu 2 , As 3 H S / HCl ( X) 2 black ppt (Y). (Y) is soluble in : (A) H 2 SO 4 (B) YAS (C) HNO 3 (D) HCl 63. There is foul smell in presence of moisture with : (A) AlCl 3 (B) Al 2 (SO 4 )3 (C) FeS (D) FeSO 4 64. Ag 2 S is soluble in NaCN due to formation of : (A) Na [ Ag(CN)2 ] (B) Ag (CN)2 (C) Na 2 [ Ag(CN)3 ] (D) Na 2 [ Ag (CN) 2 ] 65. Aqueous solution of borax reacts with two mol of acids. This is because of : (A) formation of 2 mol of B (OH)3 only Ritesh Classes Education should aim minds but reach hearts 16 9007102353/9831813135 (B) formation of 2 mol of [B (OH) 4 ] only (C) formation of 1 mol each of B (OH)3 and [B (OH) 4 ] (D) Formation of 2 mol each of [B (OH) 4 ] and B (OH)3 of which only [B (OH) 4 ] reacts with acid. 66. K 4 [Fe(CN) 6 ] can be used to dect one or more out of Fe 2 , Fe 3 , Zn 2 , Cu 2 , Cd 2 : (C) all but Fe3 (B) Fe 3 , Zn 2 , Cu 2 (A) Fe 2 , Fe 3 (D) all but Fe2 67. NH 4 SCN can be used to test one or more out of Fe 3 , Co 2 Cu 2 : (A) Fe 3 , only (B) Co 2 , Cu 2 (C) Fe 3 , Cu 2 (D) all NH / NaOH 3 68. HgCl 2 excess of KI ( A ) (B). (A) and (B) respectively are : Hg (A) K 2Hgl 4 (Nessler’s reagent), O (X) (B) (Y), (X) (C) both (X) NH 2I Hg (Iodide of Millon’s base) (D) both (Y) 69. CoCl 2 gives blue colour with NH 4 SCN in ethereal layer due to formation of : (A) (NH 4 ) 2 [Co (SCN ) 4 ] (B) (NH 4 ) 4 [Co (SCN ) 6 ] (C) (NH 4 )3 [Co (SCN ) 6 ] (D) (NH 4 ) [Co (SCN ) 4 ] 70. Aluminium sulphate (X) is slightly insoluble in water. It is converted into soluble sodium sulphate by using Na 2 CO 3 in the preparation of sodium carbonate (Y) extract. Moles of (Y), required for complete conversion of 1 mol of (X) into soluble sulphate is : (A) 1 (B) 2 (C) 3 (D) 4 71. SO 2 and CO 2 both turn lime water (A) milky, SO 2 also turns K 2 Cr2 O 7 / H (B) green while O 2 is soluble in pyrogallol (C) turing it black. These gases are to be detected in order by using these reagents. The order is : (A) (A), (B), (C) (B) (B), (C), (A) (C) (B), (A), (C) (D) (A), (C), (B) 72. AgNO 3 give white ppt with hypo changing to black after some-time. Black ppt is of : (A) Ag 2 S 2 O 3 (B) Ag 2 SO 4 (C) AgS 4 O 6 (D) Ag 2 S 73. To increase the molar solubility of CaCO 3 (s) in a saturated aqueous solution add (A) more water (B) Na 2 CO 3 (C) NaOH (D) NaHSO 4 74. Cu (OH) 2 is highly soluble in all of the following except one. The exception is : (A) H2O (B) NH 3 (aq) (C) HCl (aq) (D) HNO 3 (aq) 75. Of the following solution the one that is acidic is : (A) ZnSO 4 (aq) (B) NaAl (OH) 4 (aq) (C) NaHCO 3 (aq) (D) KNO 3 (aq) 76. Of the following oxides, all are soluble in NaOH (aq) except : Ritesh Classes Education should aim minds but reach hearts 17 9007102353/9831813135 (A) ZnO (B) Al 2O 3 (C) Fe 2 O 3 (D) SnO 2 77. There test tubes A, B, C contain Pb2 , Hg2 and Ag (but unknown). To each aqueous solution NaOH is added in excess. Following changes occur. A : Black ppt B : Brown ppt C : White ppt but dissolves in excess of NaOH A, B and C contain respectively ; 2 (A) Pb 2 , Hg 2 and Ag 2 (C) Ag , Pb2 , Hg 2 2 (B) Hg 2 , Ag , Pb 2 2 (D) Ag , Hg 2 , Pb 2 78. A mixture contains Cu 2 , Al 3 and Ni 2 . Following steps have been adopted but written in disorder I : Filter, boil off H2 S gas and add NH 4 Cl , heat and add NH 4 OH . II : Filter, add NH 4 OH and pass H2 S gas. III : Pass H2 S gas into acidified solution of mixture. Steps will be used in the following order: (A) I, II, III (B) III, I, II (C) III, II, I (D) I, III, II 79. KI gives precipitate with all the cations given : (A) Ag , Hg 22 , pb 2 (B) Cu 2 , Zn 2 , Ni 2 (C) Na , Ca 2 ,Mg 2 (D) Ag , Ca 2 , Sr 2 80. CoS (block) obtained in group IV of salt analysis is dissolved in aqua regia, treated with an excess of NaHCO 3 and then Br 2 water is added. An apple green colured stable complex is formed. It is : (A) sodium cobaltocarbonate (B) sodium cobaltibromide (C) sodium cobalticarbonate (D) sodium cobaltobromide 81. Borax on heating strongly above its melting point melts to a liquid, which then solidifies to a transparent mass commonly known as borax-bead. The transparent glassy mass consists of : (A) sodium pyroborate (B) boric anhydride (C) sodium meta-borate (D) boric anhydride and sodium metaborate 82. The compound thioacetamide has been into analytical chemistry to replace to which one of the following reagents ? (A) H2 S (B) DMG (C) YAS (D) (NH 4 ) 2 C 2 O 4 83. Some white colourless crystals heated. A cracking sound is heard and brown fumes are given off. The residue is yellow-brown in colour. When a glowing splinter is held in the fumes, it is relighted. The fumes consists of (A) O 2 (B) NO 2 (C) Cl 2 (D) NO 2 and O 2 Ritesh Classes Education should aim minds but reach hearts 18 9007102353/9831813135 84. A yellow solid known to be a single compound is completely insoluble in hot water but dissolves in hot dilute HCl to give an orange solution. When this solution is cooled, a white crystalline ppt is formed. This white ppt redissolves on heating the solution. The compound is : (A) Fe (OH)3 (B) PbCrO 4 (C) K 2CrO 4 (D) Co(OH)2 85. ‘X’ is a colourles salt giving following reactions : (i) Forms a ppt with NaOH but dissolves in excess of it. (ii) Forms a ppt with H2S in alkaline medium. (iii) Forms a yellow ppt. with AgNO3 partly soluble in ammonia. X may be: (A) AlCl 3 (B) ZnCl 2 (C) Zn (CH 3 COO ) 2 (D) ZnBr 2 86. A mixture upon adding conc. H 2 SO 4 gives orange red fumes. It may contain the anion pair : (A) CrO24 C (B) Br Cl (C) NO 3 Cl (D) Cr O 24 NO 3 87. A mixture in known to contain NO 3 and NO 2 . Before performing Ring Test for NO 3 , the aqueous solution should be made free of NO 2 . This is done by heating aqueous extract with : (A) conc. HNO 3 (B) dil.HNO 3 (C) urea (D) zinc dust 88. In borax bead test which compound is formed : (A) ortho borate (B) meta borate (C) double oxide (D) tetra borate 89. CuSO 4 when reacts with KCN forms CuCN which is insoluble in water. It is soluble in excess of KCN, due to formation of the following complex : (A) K 2 [Cu (CN) 4 ] (B) K 3 [Cu (CN) 4 ] (C) CuCN 2 (D) Cu[KCu (CN) 4 ] 90. In the separation of Cu2 and Cd2 in 2nd group of qualitative analysis of cations tetrammine copper (II) sulphate and tetraammine cadmium (II) sulphate react with KCN to from the corresponding cyanide complexes, which one of the following pairs of the complexse and their relative stabilities enables the separation of Cu2 and Cd2 ? (A) K 3 [Cu (CN) 4 ] : less stable and (B) K 3 [Cu (CN) 4 ] : more stable and K 2 [Cd (CN) 4 ] : more stable K 2 [Cd (CN) 4 ] : less stable (C) K 2 [Cu (CN) 4 ] : less stable and K 2 [Cd (CN) 4 ] : more stable (D) K 2 [Cu (CN) 4 ] : more stable and K 2 [Cd (CN) 4 ] : less stable 91. When a substance A reacts with water it produces a combustible gas B and a solution of substance C in water. When another substance D reacts with this solution of C, it also produces the same gas B on warming but D can produce gas B on reaction with dilute sulphuric acid at room temperature. A imparts a deep golden yellow colour to a smokeless flame of Bunsen burner. A, B, C and D respectively are : (A) Na, H2 , NaOH , Zn (B) K , H2 , KOH , Al (C) CaH 2 , Ca (OH)2 , Sn (D) CaC 2 , C 2H2 , Ca (OH)2 , Fe 92. When calomel reacts with NH 4 OH , we get : (A) Hg (NH 2 ) Cl Hg (B) NH 2 Hg Hg Cl (C) Hg 2O (D) HgO 93. The ion or group detected by K 2 [HgI 4 ] is : Ritesh Classes Education should aim minds but reach hearts 19 9007102353/9831813135 (A) NO (B) Cl (C) NH 2 (D) NH 4 94. Mercuric chloride is soluble in KI solution due to : (A) the formation of complex ion (B) common iodide ion (C) both (A) and (B) (D) none of the above 95. H2 S does not produce metallic sulphide with: (A) CuCl 2 (B) CoCl 2 (C) CdCl 2 96. Sodium nitroprusside can be shown by : (A) Na 2 [Fe(CN)5 NO ] (B) Na 4 [Fe (CN) 6 NO ] (D) ZnCl 2 (C) Na 4 [Fe(CN)5 NO ] (D) Na 4 [Fe(CN)6 NO ] 97. A solid compound ‘X’ on heating gives CO 2 gas and a residue. The residue mixed with water forms ‘Y’ on passing an excess of CO 2 through ‘Y’ in water, a clear solution, ‘Z’, is obtained. On boiling ‘Z’ compound ‘X’ is reformed. The compound ‘X’ is : (A) Ca (HCO 3 ) 2 (B) CaCO 3 (C) Na 2 CO 3 (D) K 2 CO 3 98. Which of the following does not gives borax bead test is : (A) chromium (B) sodium (C) cobalt (D) iron 99. The salt which produces blue colour in borax bead test is : (A) CaCl 2 (B) MnSO 4 (C) MgCO 3 (D) CoCl 2 100. On passing CO 2 through lime water it turns milky but if we pass CO 2 in excess it disappears due to the formation of : (A) CaCO 3 (B) CaHCO 3 (C) Ca (HCO 3 ) 2 (D) CaO 101. Precipitation of IV group cations takes place when H2 S passed is : (A) less ionised (B) highly ionised (C) not ionised (D) none of these 102. Nessler’s reagent is used for the test of : 2 (A) CrO 4 (B) MnO 4 103. The Nessler’s reagent contains : (A) HgI 2 (B) Hg I24 104. Nessler’s reagent is : (A) NaHgCl 4 (B) K 2HgI 4 (C) NH 4 (D) PO34 (C) Hg 2 (D) Hg 22 (C) Hg (NH 3 )2 Cl (D) K 2HgI 4 KOH 105. Which one of the following is a correct statement? (A) all metal nitrates are insoluble in water (B) solubility does not depend on temeperature (C) all metal nitrates are soluble in water (D) all metal nitrates are soluble in alcohol 106. When H2 S gas is passed in a metal sulphate solution in presence of NH 4 OH , a white precipitate is produced. The metal is identified as : (A) Zn (B) Fe (C) Pb (D) Hg Ritesh Classes Education should aim minds but reach hearts 20 9007102353/9831813135 107. The solution of sodium metal aluminate on boiling with ammonium chloride gives a white precipitate of : (A) Al 2O 3 (B) AlCl 3 (C) Al (OH)3 (D) (NH 4 )2 SO 4 . Al 2 (SO )3 108. Yellow ammonium sulphide solution is a suitable reagent used for the separation of (A) HgS and PbS (B) PbS and Bi 2 S 3 (C) Bi 2 S 3 and CuS (D) CdS and As 2 S 3 109. Three separate samples of a solution of a single salt gave these results. One formed a white precipitate with excess ammonia solution, one formed a white precipitate with dil. NaCl solution with H2 S . The salt could be (A) AgNO 3 (B) Pb (NO 3 )2 (C) Hg (NO 3 ) 2 (D) MnSO 4 110. Following does not give yellow ppt on boiling with conc. HNO 3 Amm . Molybdate – (A) AsO 34 (B) SO 24 (C) PO34 (D) None 111. On heating colourless solid A, gas B (liquid at room temp. ) and gas C are formed. A is decomposed by NaOH on heating to form gas D giving white fumes with HCl. Gas C occupies 800 ml/g at N.T.P. Hence A is – (A) NH 4NO 3 (B) NaNO 2 (C) NH 4 Cl (D) NH 4NO 2 112. In which of the following solvents, AgBr will have the highest solubility – (A) 10 3 M NaBr (B) 10 3 M NH 4 OH (C) pure water (D) 10 3 M HBr 113. Borate from green edge flame when burnt with conc. H 2 SO 4 + ethanol. Green edged flame has formula (A) (C 2H5 O)3 B (B) (C 2H5 ) BO 2 (C) (C 2H5 )3 BO3 (D) A and C 114. Mark the compound which turns black with NH 4 OH (A) Lead chloride (B) Mercurous chloride (C) Mercuric chloride (D) Silver chloride 115. When a substance A reacts with water it produces a combustible gas B and a solution of substance C water. When another substance D reacts with this solution of C, it also produces the same gas B on warming. But D can produce gas B on reaction with dilute sulphuric acid at room temperature. A imparts a deep golden yellow colour to a smokeless flame of Bunsen burner. A, B, C and D respectively are – (A) Na , H2 , NaOH , Zn (B) K , H2 , KOH , Al (C) Ca , H2 , Ca (OH) 2 , Sn (D) CaC 2 C 2H2 , Ca (OH)2 ,Fe 116. When KNO 2 is added to CO 2 salt in acetic acid medium, yellow ppt is formed. It is due to – (A) K 4 [Co(NO 2 )6 ] (B) K 3 [Co(NO 2 )6 ] (C) KCo [Co (NO 2 ) 6 ] (D) None 117. Aq. Solution contains Zn (CH 3 COO ) 2 , Cd (CH 3 COO ) 2 and Cu (CH 3 COO )2 . On passing H2 S gas, there is a precipitation of … as sulphide – (A) Zn 2 , Cd 2 (B) Cu 2 , Cd 2 (C) Zn 2 , Cu 2 (D) Zn 2 , Cu 2 , Cd 2 118. Na 2 S gives purple colour with sodium nitroprusside. Purple colour has formula – Ritesh Classes Education should aim minds but reach hearts 21 9007102353/9831813135 (A) Na 2 [Fe(CN)6 S] (C) Na 4 [Fe (CN)5 NOS ] (B) Na 2 [Fe(CN)5 NOS ] (D) Ne [Fe (CN)5 NOS ] 119. Which one of the following statement is correct? (A) From a mixed precipitate of AgCl and AgI , ammonia solution dissolves only AgCl (B) Ferric ions give a deep green precipitate on adding potassium ferrocyanide solution (C) On boiling a solution having K , Ca 2 and HCO 3 ions we get a precipitate of K 2 Ca (CO 3 ) 2 (D) Manganese salts give a violet borax bead test in the reducing flame 120. A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the solution, a white precipitate is obtained which does not dissolve in dil. HNO 3 . The anion could be – (A) CO32 (B) Cl 121. CaC 2 O 4 is soluble in – (A) HCl (B) H 2 SO 4 (C) SO32 (D) S 2 (C) CH 3 COOH (D) All 122. Which of the following compounds dose not leave any residue on heating – (A) Pb(NO 3 )2 (B) NH 4NO 3 (C) Cu (NH 3 ) 2 (D) NaNO 3 123. Mixture of two salts are not soluble in water but soluble in dilute HCl solution. Mixture can be – (A) AgNO 3 and KBr (B) BaCO 3 and ZnS (C) FeCl 3 and CaCO 3 (D) Mn (NO 3 )2 and MgSO 4 124. Three samples of the same salts are taken separately. Excess of NH 4 OH gives white precipitate with first sample. Second sample gives white precipitate with NaCl. Third sample black precipitate when H2 S gas is passed through the solution. Possible salt is – (A) AgNO 3 (B) Pb (NO 3 )2 (C) Hg (NO 3 ) 2 (D) MnSO 4 SECTION – B (Multiple Options Correct) : 125. The value of nH of CH 3 COOH and NaOH is (A) equal to 57.3 kJ mol 1 (B) Less negative than 57.3 kJ mol 1 (C) more negative than 57.3 kJ mol 1 (D) depends on water equivalent of calorimeter system. 126. Pick up the correct statement about acid-base indicators (A) Phenolphthalein can be used as indicator in all acid base titrations (B) Phenolphthalein does not work well in HCl-NaOH titration (C) Methyl orange cannot be used as indicator in NaOH HCl titration (D) All acid-base indicator are acid/bases themselves. 127. A white fluffy salt gives effervescence with dilute H 2 SO 4 . Its residue remains white in charcoal cavity test but in cobalt nitrate test a pink mass is formed. The salt is likely to be (A) BaCO 3 (B) MgCO 3 (C) Na 2 CO 3 (D) CaCO 3 . Ritesh Classes Education should aim minds but reach hearts 22 9007102353/9831813135 128. During analysis of basic radicals of a mixture containing cations of group V, a solution of NaHCO 3 is added instead of Na 2CO 3 along with NH 4 OH . This would result in formation of (A) White ppt. (B) Yellow ppt. (C) Brick red ppt. (D) No ppt at all. 129. Ceric ammonium nitrate solution is added ethyl alcohol solution. The pink coloured solution is obtained due to the formation of (A) (NH 4 ) 2 NO 3 (B) Ce (NO 3 ) 4 (C) brown gas NO 2 (D) (C 2H5 OH)2 Ce (NO 3 )6 . 130. Which of the following forms cloudiness with Lucas reagent in minimum time? (A) Phenylmethanal (B) Butan-2-ol (C) 2-methylpropan-2-ol (D) Benzenol. 131. Which of the following compound will give yellow precipitate on shaking with carbon disulphide? (A) Potassium phenolate (B) K C CH (C) Potassium ethoxide (D) (CH 3 ) 2 CO . 132. Which of the following is purple coloured species? (A) [Fe (OC 6H5 ) 6 ]3 (B) K O C 6H5 (C) Pb (NO 3 )2 (D) K 2 Cr2 O 7 133. Which operation will not help the preparation of p-nitroacetanilide? (A) Using a mixture conc. H 2 SO 4 and conc. HNO 3 (B) Refluxing the contents over sand bath (C) Keeping the contents of the reaction in ice bath (D) Recrystallisation of the product formed. 134. An aqueous solution which of MCl 2 containing excess of KCN when treated with H2 S precipitates MS only if ‘M’ is(A) Ni (B) Co (C) Cu (D) Cd 135. NH 4 OH dissolves which of the following completely or partially(A) AgCl (B) AgBr (C) PbSO 4 (D) AgI 136. Reddish brown gas is obtained when the following are treated with conc. H 2 SO 4 (A) Br (B) NO 3 137. Borax bead test is give by(A) Co2 (B) Zn 2 (C) NO 2 (D) I (C) Cu2 (D) Ni 2 138. Conc. H 2 SO 4 will not give any gas with(A) ZnSO 4 (B) Barium phosphate (C) Magnesium borate (D) Sodium oxalate. 139. Which of the following react with dil. H 2 SO 4 (A) CaCO 3 (B) KNO 2 (C) Na 2 S (D) ZnSO 3 140. Diphenylamine reagent gives a deep blue colour with a solution. It contains – (A) Sn2 (B) NO 2 (C) NO 3 (D) Fe3 141. In II B group of basic radicals the yellow ppt. are given by – (A) As 3 (B) Sb3 (C) Sn 4 Ritesh Classes Education should aim minds but reach hearts 23 (D) Sn2 9007102353/9831813135 142. Black sulphides are formed by – (A) Cu2 (B) Sb3 (C) Pb 2 (D) Bi 3 (C) Ag (D) Cu2 (C) Ag (D) Ca2 143. KI solution identifies(A) Hg 2 2 (B) Pb 2 144. K 2CrO 4 is used to identify – (A) Pb 2 (B) Ba 2 SECTION – C (Assertion & Reason Type) : The following questions 1 to 12 consists of two statements each, printed as Assertion and Reason. While answering these questions you are to choose any one of the following four responses. (a) If both Assertion and Reason are true and the Reason is correct explanation of the Assertion. (b) If both Assertion and Reason are true but Reason is not correct explanation of the Assertion. (c) If Assertion is true but the Reason is false. (d) If Assertion is false but Reason is true. (e) Both assertion and reason are false. 145. Assertion Reason : : Coloured cations can be identified by borax-bead test. Transparent bead (NaBO 2 B 2 O 3 ) forms coloured bead with coloured cation. 146. Assertion : : Unreacted AgNO 3 of photographic plate is removed by Na 2 S 2 O 3 (hypo). Na 3 [ Ag(S 2 O 3 )2 ] is soluble complex. : CO 2 containing H2 O changes yellow CrO 24 into Cr2 O 72 . : Aq CO 2 is acidic (H2CO 3 Reason 147. Assertion Reason 148. Assertion Reason 149. Assertion Reason 150. Assertion : : : : H HCO 3 ) Cu2 and Cd2 solution is complexed by addition of KCNS. On passing H2 S gas stable complex [Cu (CN) 4 ]3 is not affected. NO 2 is decomposed by urea in the mixture on NO 3 and NO 2 . NO 3 interferes in the ring test of NO 2 : Basic radicals (cation) have been divided into groups based on K sp values. : Mostly alkali salts are water soluble. 151. Assertion Reason : : PbCl 2 and AgCl precipitates can be separated by aq NH 3 . PbCl 2 precipitates change to soluble complex [Pb (NH 3 ) 4 ] Cl 2 . 152. Assertion Reason : : PbCl 2 and Hg 2 Cl 2 precipitates can be separated by hot water. Hg 2 Cl 2 is blackened by aq NH 3 . Reason Ritesh Classes Education should aim minds but reach hearts 24 9007102353/9831813135 153. Assertion Reason 154. Assertion Reason : : : When H2S(g) is passed into aqueous Zn (CH 3 COO ) 2 solution, zinc is precipitated as ZnS. CH 3 COOH is produced in the reaction which cannot dissolve ZnS formed. When H 2 S ( g) is passed into aqueous ZnCl 2 , solution, ZnS is precipitated. ZnS is insoluble in dil. HCl. 155. Assertion Reason : : Borax bead test is applicable only to coloured salts. In borax bead test, colured salts are decomposed to give coloured metal metaborates. 156. Assertion Reason : : Sulphide gives purple colour with sodium nitroprusside solution. Sodium nitroprusside is a complex compound. 157. Assertion : Phosphates are identified by the yellow precipitate obtained on adding ammonium molybdate solution. Ammonium phosphomolybdate is a yellow compound. Reason 158. Assertion Reason 159. Assertion Reason : : : : Boiling a solution containing Cl , Br and I with potassium persulphate, violet and brown vapours apper. Br and I are oxidised to Br 2 and I 2 but Cl is not oxidised. : Cu2 and Cd2 are separated from each other by first adding. KCN solution and then passing H2 S gas. : KCN reduces Cu2 to Cu and forms a complex with it. SECTION – D (True & False) : 160. There is precipitation of solute AB if its ionic product is greater than K sp value, i.e., [ A ] [B] K sp 161. If K sp of M (OH)3 is 1 10 12 then 0.001 M. M3 is precipitated at a pH 9 . 162. BaBr 2 gives yellow ppt with AgNO 3 as well as with K 2 CrO 4 . 163. AlCl 3 is soluble in excess of NaOH forming sodium meta-aluminate Na [ Al (OH) 4 ] . 164. K 4 [Fe(CN) 6 is used to test Cu 2 , Fe 3 , Zn 2 and Cd2 ions. 165. When KNO 2 and CH 3 COOH is added to CoCl 2 solution, yellow ppt of K 4 Co(NO 2 )6 is formed. 166. Alkaline solution of NH 4 Cl gives brown ppt with K 2HgI 4 . 167. If acidified solution of K 2 Cr2 O 7 turns green on addition of a salt then salt may contain Fe2 . Ritesh Classes Education should aim minds but reach hearts 25 9007102353/9831813135 168. NaOH can be used to separate Al (OH)3 and Fe(OH)3 . 169. NH 4 Cl can be replaced by (NH 4 )2 SO 4 in group III. SECTION – E (Fill in the blanks) : 170. Separation of basic radicals is based on ________ (a) _______ and _________ (b) ________ 171. Cd2 and Cu2 are separated by _______ (a) _______ formation using _____ (b) ______ in which ________ (c) _______ is more stable than ________ (d) _______ on passing H2 S gas _______ (e) _______ is precipitated. 172. PbCl 2 is soluble in ________ (a) _______ , AgCl is soluble in ______ (b) ______ ; while Hg 2 Cl 2 is _______ (c) _______ by NH 3 . 173. Fe (OH)3 and Al (OH)3 ppt can be separated by ______ (a) ______ when _______ (b) _______ becomes soluble due to the formation of ______ (c) _____ , and _______ (d) _____ remains insoluble. 174. Cr (OH)3 is made soluble in NaOH in presence of _____ (a) ______ when _______ (b) ______ of ______ (c) _______ colour is formed and gives yellow ppt of ______ (d) _______ when _______ (e) ______ is added. 175. Acidified KMnO 4 can be decolorised by _____ (a) _____ . 176. FeC 2O 4 can decolorise acidified KMnO 4 due to the oxidation of _____ (a) _____ and _____ (d) _____ . 177. A reagent that can detect any of Cu 2 , Fe 3 , Zn 2 and Cd 2 is ______ (a) ______ . 178. HgCl 2 gives orange ppt with ______ (a) ______ , which dissolves in excess of it forming _____ (b) _______ called ______ (c) ______ . 179. NH 4 SCN gives red colour with ______ (a) ______ due to the formation of ______ (b) _____. 180. Gas that turns lime water milky and acidified K 2 Cr2 O 7 green is _____ (a) ______ . 181. Yellow ppt of _____ (a) ______ is formed when CoCl 2 reacts with excess of KNO 2 in presence of CH 3 COOH . 182. BaBr 2 in aq solution gives yellow ppt with _____ (a) _____ as well as with _____ (b) _____ . 183. As 2 S 3 is soluble in (NH 4 ) 2 S 2 (yellow ammonium sulphide) due to the formation of _____ (a) _____ . Ritesh Classes Education should aim minds but reach hearts 26 9007102353/9831813135 184. Hypo gives ______ (a) ______ ppt with AgNO 3 which changes to _______ (b) _______ . SECTION – F (Match the Column) : 185. (a) (b) (c) Column – I Co 2 and Ni 2 Al 3 Ag and Cr 2 3 and Hg 2 2 2 (d) Cu (e) Ca 2 and Sr 2 and Cd (p) Column – II Group – II (q) Group – I (r) Group – III (s) Group – V (t) Group – IV Column – I (a) Ring test (p) Column – II NO 2 (b) Chromyl chloride Test Green edged flame With ethylacohol (q) BO3 3 (r) NO 3 Canary yellow Precipitate Starch iodide Paper test (s) PO43 (t) Cl 186. (c) (d) (e) (a) (b) (c) (d) (e) (f) Column – I Aluminium Tin Lead Iron Copper Zinc (p) (q) (r) (s) (t) (u) Column – II anglestite siderite corundum calamine cassiterite azurite (a) (b) (c) Column – I SnS 2 Chrome yellow NH 3 (p) (q) (r) Column – II Nessler’s reagent white pigment Mosaic gold (d) (e) (f) NO 3 ZnO Pb(C 2H5 ) 4 (s) (t) (u) antiknocking PbCrO 4 FeSO 4 H2 SO 4 (a) (b) Column – I K ions. Fe3 ions (p) (q) Column – II excess of KI(aq) HCl (aq) (c) (d) Cu2 ions HgCl 2 (aq.) (r) (s) sodium cobaltinitrite starch solution 187. 188. 189. Ritesh Classes Education should aim minds but reach hearts 27 9007102353/9831813135 (e) (f) PbNO 3 (aq) I2 (aq) (t) (u) SCN ions ferrocyanide ions SECTION – G (Comprehension) : Passage # 1 Preasence of Fe 3 in an aqueous solution can be made by addition of sodium acetate (in excess) when a reddish brown colour is formed. Read the above short write up & answer the following question – 190. Reddish brown colour is due to formation of – (A) [Fe(H2O) 4 (CH 3 COO )2 ] (B) [Fe(CH 3 COO )6 ]3 (D) [Fe 2 (H2 O) 4 (CH 3 COO ) 4 ] 2 (C) [Fe (CH3 COO )3 ] 191. Excess of sodium acetate is added in the above test. It is because – (A) It act as buffer to control pH of the reaction, otherwise reaction is made reversible (B) It makes the solution alkaline which destroys acidic effect if any (C) Sodium acetate has low k sp value (D) Sodium acetate has high k sp values 192. Presence of Fe 3 can also be detected by ________ when ________ is formed – (A) KCNS , Fe(CNS )3 ....... blood red (B) KCNS , Fe(CNS ) Cl 2 ....... blood red (C) KCNS , [ Fe(CNS )2 Cl] ....... blood red (D) KCNS , K 3 [ Fe(CN)6 ] ....... blue ppt. 193. A blue solution is formed when potassium ferro cyanide in excess is added to aqueous ferric chloride solution. This blue colour is of – (A) (B) (C) (D) II III K Fe[Fe(CN)6 ] Fe [Fe (CN) 6 ] 3 Fe 3 [Fe (CN)6 ] 2 none of these III II or K [Fe(CN)6 ] Passage # 2 A coloured solution known to contain two metal ions, was treated with excess cold sodium hydroxide solution. When filtered a whitish solid, slowly changing to brown was retained on the filter paper and a colourless solution collected as filtrate. Drop wise addition of hydrochloric acid to the filtrate produced a white precipitate which dissolves in excess acid. Treatment of residue from filter paper with a solution of a strong oxidiser produced a reddish-violet solution. 194. Indicate any pairs of ions which on testing as above leads to the observed changes – (A) Zn 2 & Mn 2 ions (B) Zn 2 & Mg 2 ions (C) Mn 2 & Mg 2 ions (D) Fe 2 & Zn 2 ions 195. Filtrate obtained after separation of white solid contains – (A) ZnO (B) Na 2 ZnO 2 (C) MnO (D) Na 2MnO 2 196. White solid changing to brown is due to formation of – Ritesh Classes Education should aim minds but reach hearts 28 9007102353/9831813135 (A) Mn (OH) 2 (B) MgO (C) Zn (OH) 2 (D) MnO 2 197. Reddish-violet solution obtained by oxidation is of – (A) ZnO 2 2 (B) MnO 4 2 (C) MnO 4 (D) MnO 2 198. Reddish violet solution is decolourised by – (A) SO3 2 , C2O4 2 , Fe 2 (B) SO4 2 , HCO3 2 , Fe 3 (C) NO 2 , SO4 2 , Fe 2 (D) H2O2 , C2O4 2 , CO3 2 Passage # 3 When a white crystalline compound (x) is heated with K 2 Cr2 O 7 and concentrated H2SO 4 , a reddish brown gas (A) is evolved. On passing (A) into caustic soda solution, a yellow coloured solution of (B) is obtained. Neutralizing the solution of (B) with CH 3 COOH and on subsequent addition on (CH 3 COO )2 Pb a yellow precipitate of (C) is obtained. When (X) is heated with NaOH solution, a solution, a colourless gas is evolved and on passing this gas into K 2HgI 4 a reddish brown precipitate (D) is formed. 199. The aqueous solution of (X) is – (A) Acidic (B) Neutral (C) Basic (D) Can not be predicted 200. What is yellow coloured solution (B) which is obtained in above context – (A) Na 2CrO 4 (B) PbCrO 4 (C) Na 2 Cr2 O 7 (D) CrO 5 201. Reddish brown ppt. (D) is – (A) NH 2HgI HgI (B) NH 2HgOHgI (C) NH 2HgO HgO (D) none of these 202. What is reddish brown gas formed by reaction of (X) with K 2 Cr2 O 7 (A) NO 2 (B) Cl 2 (C) CrO 2 Cl 2 (D) none of these 203. What is the yellow ppt. formed in above context – (A) PbCl 2 (B) PbCrO 4 (C) Sulphur (D) Na 2CrO 4 Passage # 4 Nitrogen forms a series of oxides with oxygen. These are N2O , NO , N2O 3 , NO 2 and N2O 5 . 204. Which of the oxide of nitrogen is easily dimerized? (A) N2O (B) NO (C) NO 2 (D) N2O 5 205. Which of the oxide of nitrogen exists as ionic solid? (A) N2O (B) NO (C) NO 2 (D) N2O 5 206. Which of the oxide is considered to be mixed anhydride of nitrous and nitric acids? (A) N2O (B) NO (C) N2O 4 (D) N2O 5 Passage # 5 Nitric oxide is absorbed by a cold solution of ferrous sulphate due to the formation of the dark brown nitrosyl complex ion, [Fe (NO ) (H2O)6 ] 2 . Ritesh Classes Education should aim minds but reach hearts 29 9007102353/9831813135 207. The number of unpaired electrons in the complex ion is (A) 2 (B) 3 (C) 4 (D) 5 208. The magnetic moment of the complex in Bohr magneton is (A) 3 (B) 6 (C) 15 (D) 35 EXERCISE – II (IIT previous years questions) Fill in the blanks : 209. If metal ions of group III are precipitated by NH 4 Cl and NH 4 OH without prior oxidation by conc. HNO 3 _______ is not completely precipitated. 210. The formula of the deep red liquid formed on warming dichromate with KCl in concentrated sulphuric acid is _________ True / False : 211. Addition of ammonium chloride to a solution containing ferric and magnesium ions is essential for selective precipitation of ferric hydroxide by aqueous ammonia. 212. From the acidic solution containing copper (+2) and zinc (+2) ions, copper can be selectively precipitated using sodium sulphide. Single Option : 213. The ion that cannot be precipitated by both HCl and H2 S is (A) Pb2 (B) Cu (C) Ag (D) Sn2 214. Which one among the following pairs of ions cannot be separated by H2 S in dilute hydrochloric acid? (A) Bi 3 , Sn 4 (B) Al 3 , Hg 2 (C) Zn 2 , Cu 2 (D) Ni 2 , Cu 2 215. Read the following statement and explanation and answer as per the options given below : Assertion : A very dilute acidic solution of Cd2 and Ni 2 gives yellow precipitate of CdS on passing hydrogen sulphide. Reason : Solubility product of CdS is more than that of NiS. (A) If both assertion and statement are correct and statement is an explanation of assertion. (B) If assertion is correct and statement is wrong, statement is not an explanation of assertion. (C) If assertion is wrong and statement is correct, statement is not an explanation of assertion. (D) If both assertion and statement are wrong and statement is not explanation of assertion. 216. An aqueous solution contains Hg2 , Hg22 , Pb2 and Hg 2 . The addition of HCl (6N) will precipitate : (A) Hg 2 Cl 2 only (B) PbCl 2 only (C) PbCl 2 and Hg 2 Cl 2 (D) PbCl 2 and HgCl Ritesh Classes Education should aim minds but reach hearts 30 9007102353/9831813135 217. The only cations present in a slightly acidic solution are Fe 3 , Zn 2 and Cu2 . The reagent that when added in excess to this solution would identify to separate Fe3 in one step is (A) 2M HCI (B) 6 M NH 3 (C) 6 M NaOH (D) H2S gas 218. Read the following statement and explanation and answer as per the options given below : Assertion : Sulphate is estimated as BaSO 4 and not as MgSO 4 . Reason : Ionic radius of Mg 2 is smaller than that of Ba 2 . (A) If both assertion and reason are correct and reason is the correct explanation of the assertion. (B) If both assertion and reason are correct, but reason is not the correct explanation of the assertion. (C) If assertion is correct but reason is incorrect. (D) If assertion is incorrect but reason is correct. 219. Identify the correct order of solubility of Na 2 S , CuS and ZnS in aqueous medium (A) CuS ZnS Na 2 S (B) ZnS Na 2S CuS (C) Na 2 S CuS ZnS (D) Na 2 S ZnS CuS 220. An aqueous solution of a substance gives a white precipitate on treatment with dilute hydrochloric acid, which dissolves of heating. When hydrogen sulphide is passed through the hot acidic solution, a black precipitate is obtained. The substance is a (A) Hg 22 salt (B) Cu2 salt (C) Ag salt (D) Pb2 salt 221. A gas ‘X’ is passed through water to form a saturated solution. The aqueous solution on treatment with silver nitrate gives a white precipitate. The saturated aqueous solution also dissolves magnesium ribbon with evolution of a colourless gas ‘Y’. Identify ‘X’ and ‘Y’. (A) X CO 2 , Y Cl 2 (B) X Cl 2 , Y CO 2 (C) X Cl 2 , Y H2 (D) X H2 , Y Cl 2 222. [ X] H2SO 4 [ Y] a colourless gas with irritating smell, [ Y] K 2Cr2O 7 H2SO 4 green solution. [X] and [Y] are : (A) SO32 , SO 2 (B) Cl , HCl (C) S 2 , H2 S (D) CO32 , CO2 223. A solution which is 10 3 M each in Mn 2 , Fe 2 , Zn 2 and Hg 2 sulphide ion. If K sp of MnS, FeS, ZnS is treated with 10 16 M and HgS are 10 15 , 10 23 , 10 20 and 10 54 respectively, which one will precipitate first? (A) Fes (B) MgS (C) HgS (D) ZnS 224. A metal nitrate reacts with KI to give a black precipitate which on addition of excess of KI is converted into orange colour solution. The cation of the metal nitrate is (A) Hg 2 (B) Bi 3 (C) Pb 2 (D) Cu 225. A solution when diluted with H2O and boiled, gives a white precipitate. On addition of excess NH 4 Cl / NH 4 OH , the volume of precipitate decreases leaving behind a white gelatinous precipitate. Identify the precipitate which dissolves in NH 4 OH / NH 4 Cl (A) Al (OH)3 (B) Zn (OH) 2 (C) Ca(OH)2 (D) Mg (OH) 2 Ritesh Classes Education should aim minds but reach hearts 31 9007102353/9831813135 226. A solution of a metal ion when treated with KI gives a red precipitate which dissolves in excess KI to give a colourless solution. Moreover, the solution of metal ion on treatment with a solution of cobalt (II) thiocyanate gives rise to a deep blue crystalline precipitate. The metal ion is (A) Pb2 (B) Hg 2 (C) Cu2 (D) Co2 Multiple Options : 227. The reagents, NaCl and aqueous NH 3 will precipitate (A) Ca2 (B) Al 3 (C) Bi 3 (D) Mg 2 (E) Zn 2 228. Which of the following statement(s) is (are) correct when a mixture of NaCl and K 2 Cr2 O 7 is gently warmed with conc. H2 SO 4 ? (A) A deep red vapour is evolved (B) The vapours when passed into NaOH solution gives a yellow solution of Na 2CrO 4 (C) Chlorine gas is evolved (D) Chromyl chloride is formed. 229. Which of the following statement(s) is (are) correct with reference to the ferrous and ferric ions? (A) Fe3 gives brown colour with potassium ferrocyanide. (B) Fe3 gives blue precipitate with potassium ferrocyanide. (C) Fe3 gives red colour with potassium thiocyanate. (D) Fe3 gives brown colour with ammonium thiocyanate. Subjective Problems : 230. Account for the following. Limit your answer to two sentences : The precipitation of second group sulphides in qualitative analysis is carried out with hydrogen sulphide in presence of hydrochloric acid and not nitric acid. 231. Compound A is a light green crystalline solid. It gives the following tests : (i) It dissolves in dilute sulphuric acid. No gas is produced. (ii) A drop of KMnO 4 is added to the above solution. The pink colour disappears. (iii) Compound A is heated strongly. Gases B and C, with pungent smell, come out. A brown residue D is left behind. (iv) The gas mixture (B) and (C) is passed into a dichromate solution. The solution turns green. (v) The green solution from step (iv) gives a white precipitate E with a solution of barium nitrate. (vi) Residue D from step (iii) is heated on charcoal in a reducing flame. It gives a magnetic substance. Name the compounds A, B, C, D and E 232. When 16.8 g of white solid X were heated, 4.4 g of acid gas. A that turned lime water milky was driven off together with 1.8 g of a gas B which condensed to a colourless liquid. The solid Ritesh Classes Education should aim minds but reach hearts 32 9007102353/9831813135 that remained, Y, dissolved in water to give an alkaline solution, which with excess barium chloride solution gave a white precipitate Z. The precipitate effervesced with acid giving off carbon dioxide. Identify A, B and Y and write down the equation for the thermal decomposition of X. 233. A mixture of two salts was treated as follows : (i) The mixture was heated with manganese dioxide and concentrated sulphuric acid when yellowish green gas was liberated. (ii) The mixture on heating with sodium hydroxide solution gave a gas which turned red litmus blue. (iii) Its solution in water gave blue precipitate with potassium ferrocyanide and red colouration with ammonium thiocyanate. (iv) The mixture was boiled with potassium hydroxide and the liberated gas was bubbled through an alkaline solution of K 2HgI 4 to give brown precipitate. Identify the two salts. Give ionic equations for reactions involved in the tests (i), (ii) and (iii). 234. A hydrated metallic salt A, light green in colour, on careful heating gives a white anhydrous residue B. B is soluble in water and its aqueous solution reacts with NO to give a dark brown compound C. B on strong heating gives a brown residue D and a mixture of two gases E and F. The gaseous mixture when passed through acidfied permanganate, discharges the pink colour and when passed through acidified BaCl 2 solution gave a white precipitate. Identify A, B, C, D, E and F. 235. When 20.02 g of a white solid X is heated 4.4 g of an acid gas A and 1.8 g of a natural gas B are evolved, leaving behind a solid residue Y of weight 13.8g. A turns lime water milky and B condenses into a liquid which changes anhydrous copper sulphate blue. The aqueous solution of Y is alkaline to litmus and gives 19.7 g of white precipitate Z with barium chloride solution. Z gives carbon dioxide with an acid. Identify A, B, X, Y and Z. 236. The gas liberated on heating a mixture of two salts with NaOH, gives a reddish brown precipitate with an alkaline solution of K 2HgI 4 . The aqueous solution of the mixture on treatment with BaCl 2 gives a white precipitate which is sparingly soluble in conc. HCl. On heating the mixture with K 2 Cr2 O 7 and conc. H 2 SO 4 , red vapours A are produced. The aqueous solution of the mixture gives a deep blue colouration in the given mixture and write the balanced equations for the formation of A and B. 237. A light bluish green crystalline compound responds to the following tests : (i) Its aqueous solution gives a brown precipitate or colour with alkaline K 2 [HgI 4 ] solution. (ii) Its aqueous solution gives a blue colour with K 3 [Fe (CN)6 ] solution. (iii) Its solution in hydrochloric acid gives a white precipitate with BaCl 2 solution. Identify the ions present and suggest the formula of the compound. 238. An orange solid (A) on heating gave a green residue (B), a colourless gas (C) and water vapour. The dry gas (C) on passing over heated Mg gave a white solid (D). (D) on reaction with water gave a gas (E) which formed dense white fumes with HCl. Identify (A) to (E) and give reactions involved. 239. A is a binary compound of a univalent metal, 1.422 g of a reacts completely with 0.321 g of sulphur in an evacuated and sealed tube to give 1.743 g of a white crystalline solid. B, that forms a hydrated double salt, C with Al 2 (SO 4 )3 . Identify A, B and C. Ritesh Classes Education should aim minds but reach hearts 33 9007102353/9831813135 240. A scarlet compound A is treated with conc. HNO 3 to give a chocolate brown precipitate B. The precipitate is filtered and the filtrate is neutralised with NaOH. Addition of KI to the resulting solution gives a yellow precipitate C. The precipitate B on warming with conc. HNO 3 in the presence of Mn (NO 3 ) 2 produces a pink-coloured solution due to the formation of D. Identify A, B, C and D. Write the reaction sequence. 241. Calcium burns in nitrogen to produce a white power which dissolves in sufficient water to produce a gas (A) and an alkaline solution. The solution on exposure to air produces a thin solid layer of (B) on the surface. Identify the compounds A and B. 242. A colourless inorganic salt (A) decomposes completely at about 250 C to give only two products, (B) and (C), leaving no residue. The oxide (C) is a liquid at room temperature and neutral to moist litmus paper while the gas (B) is a neutral oxide. White phosphorus burns in excess of (B) to produce a strong white dehydrating agent. Write balanced equations for the reactions involved in the above process. 243. During the qualitative analysis of a mixture containing Cu 2 and Zn 2 ions. H2 S gas is passed through an acidified solution containing these ions in order to test Cu2 alone. Explain briefly. 244. A white solid is either Na 2 O or Na 2O 2 . A piece of red litmus paper turns white when it is dipped into a freshly made aqueous solution of the white solid. (i) Identify the substance and explain with balanced equation. (ii) Explain what would happen to the red litmus if the white solid were the other compound. 245. An aqueous solution containing one mole of Hgl 2 and two moles of Nal is orange in colour. On addition of excess Nal the solution becomes colourless. The orange colour reappears on subsequent addition of NaOCl. Explain with equation. 246. An aqueous blue coloured solution of a transition metal sulphate reacts with H2 S in acidic medium to give a black precipitate A, which is insoluble in warm aqueous solution of KOH. The blue solution on treatment with KI in weakly acidic medium turns yellow and produces a white precipitate B. Identify the transition metal ion. Write the chemical reactions involved in the formation of A and B. 247. Write the chemical reactions associated with the ‘borax bead test’ of cobalt (II) oxide. 248. A white substance (A) reacts with dilute H 2 SO 4 to produce a colourless gas (B) and a colourless solution (C). The reaction between (B) and acidified K 2 Cr2 O 7 solution produces a green solution and a slightly coloured precipitate (D). The substance (D) burns in air to produce a gas (E) which reacts with (B) to yield (D) and a colourless liquid. Anhydrous copper sulphate is turned blue on addition of this colourless liquid. Addition of aqueous NH 3 or NaOH to (C) produces first a precipitate, which dissolves in the excess of the respective reagent to produce a clear solution in each case. Identify (A), (B), (C), (D) and (E). Write the equations of the reactions involved. 249. When a white crystalline compound X is heated K 2 Cr2 O 7 and concentrated H 2 SO 4 , a reddish brown gas A is evolved. On passing A into caustic soda solution, a yellow coloured solution of B is obtained. Neutralizing the solution B with acetic acid and on subsequent addition of lead acetate, a yellow precipitate C is obtained. When X is heated with NaOH Ritesh Classes Education should aim minds but reach hearts 34 9007102353/9831813135 solution, a colourless gas is evolved and on passing this gas into K 2HgI 4 solution, a reddish brown precipitate D is formed. Identify A, B, C, D and X. Write the equations of reactions involved. 250. A mixture consists of A (yellow solid) and B (colourless solid) which gives lilac colour in flame. (a) Mixture gives black precipitate C on passing H2S( g) through its aqueous solution. (b) C is soluble in aquq-regia and on evaporation of aqua-regia and adding SnCl 2 gives grayish black precipitate D. The salt solution with NH 4 OH gives a brown precipitate. (i) The sodium carbonate extract of the salt with CCl 4 / FeCl 3 gives a violet layer. (ii) The sodium carbonate extract gives yellow precipitate with AgNO 3 solution which is insoluble in NH 3 . Identify A and B, and the precipitates C and D. It is recommended that you look at the answer key provided in the next page only once you have attempted the questions. ANSWER KEY 51. (D) 52. (C) 53. (C) 59. (A) 60. (D) 61. (C) 67. (B) 68. (A) 69. (A) 75. (A) 76. (C) 77. (B) 83. (D) 84. (B) 85. (D) 91. (A) 92. (A) 93. (D) 99. (B) 100. (C) 101. (B) 107. (C) 108. (D) 109. (B) 115. (A) 116. (B) 117. (D) 123. (B) 124. (B) 125. (B) 131. (C) 132. (A) 133. (B) 139. (ABD) 140. (BCD) 141. (AC) 147. (A) 148. (B) 149. (C) 155. (A) 156. (B) 157. (A) 163. (T) 164. (T) 165. (F) 170. common ion, K sp values 54. (A) 55. (C) 56. (A) 57. (B) 58. (C) 62. (C) 63. (C) 64. (A) 65. (B) 66. (D) 70. (C) 71. (C) 72. (D) 73. (D) 74. (A) 78. (B) 79. (A) 80. (C) 81. (D) 82. (A) 86. (A) 87. (C) 88. (B) 89. (B) 90. (B) 94. (A) 95. (B) 96. (A) 97. (B) 98. (B) 102. (C) 103. (B) 104. (D) 105. (C) 106. (A) 110. (B) 111. (B) 112. (B) 113. (D) 114. (B) 118. (A) 119. (A) 120. (B) 121. (A) 122. (B) 126. (D) 127. (B) 128. (D) 129. (D) 130. (A) 134. (D) 135. (A, B) 136. (ABC) 137. (ACD) 138. (ABC) 142. (ACD) 143. (BC) 144. (ABC) 145. (A) 146. (A) 150. (B) 151. (C) 152. (B) 153. (A) 154. (E) 158. (A) 159. (B) 160. (T) 161. (T) 162. (T) 166. (T) 167. (T) 168. (T) 169. (F) 171. complex formation effect, KCN, [K 3 [Cu (CN) 4 ] 172. hot water, aq NH 3 , black ened 173. NaOH , Al (OH)3 , NaAlO 2 , FeOH 3 174. H2O 2 , Na 2 , CrO 4 , yellow, prCrO 4 , (CH 3 COO )2 Pb 175. Fe2 or (C2O4 2 , SO2 etc ) 177. K 4 [Fe (CN)6 ] 178. KI , K 2HgI 4 , Nessler’s Reagent 176. Fe2 , C O 2 2 4 181. 182. K 2 CrO 4 , AgNO 3 183. K 3 [CO (NO 2 ) 6 ] (NH 4 )3 AsS 4 185. (a)-(p), (b)-(r), (c)-(q), (d)-(p), (e)-(s) 184. white ( Ag 2 S 2 O 3 ), black ( Ag 2 S) 186. (a)-(r), (b)-(t), (c)-(q), (d)-(s), (e)-(p) 187. (a)-(r), (b)-(t), (c)-(t), (d)-(q), (e)-(u), (f)-(s) 188. (a)-(r), (b)-(t), (c)-(p), (d)D-(t), (p)-(q), (f)-(s) 189. (a)-(r), (b)-(t), (c)-(u), (d)-(p), (p)-(q), (f)-(s) 190. (C) 191. (A) 192. (A) 193. (A) 194. (A) 195. (B) 196. (D) 197. (C) 198. (A) 199. (A) 200. (A) 201. (B) 202. (C) 203. (B) 204. (C) 205. (B) 3 206. (C) 207. (B) 208. (C) 211. (T) 212. (T) CrO Cl 210. 2 2 209. Fe 179. Fe 3 , [Fe (SCN )] 180. SO 2 Ritesh Classes Education should aim minds but reach hearts 35 9007102353/9831813135 213. (D) 221. (C) 229. (BC) 214. (A) 215. (B) 216. (C) 217. (B) 218. (B) 219. (D) 220. (D) 222. (A) 223. (C) 224. (B) 225. (B) 226. (B) 227. (AB) 228.(ABD) 232. CO 2 , H2 O , NaHCO 3 , Na 2CO 3 , BaCO 3 233. FeCl 2 , NH 4 Cl A B X Y Z 234. FeSO 4 , 7 H2O , FeSO 4 , FeSO 4 , NO , Fe 2O 3 , SO 2 , SO 3 235. CO 2 , H2O , KHCO 3 , K 2CO 3 , BaCO 3 A B C D E F A B X Y Z 236. NH 4 , Fe 2 , SO 24 , Cl 237. NH 4 , Fe 2 , SO 24 , FeSO 4 (NH 4 )2 SO 4 . 6 H2 O 238. (NH 4 )2 Cr2O 7 , Cr2O3 , N2 , Mg 3N2 , NH 3 239. KO 2 , K 2SO 4 , Al 2 (SO 4 )3 , 24 H2O A B C D E A B C D 240. Pb 3 O 4 , PbO 2 , PbI 2 241. NH 3 , CaCO 3 244. (i) Na 2 C 2 , (ii) turns red litmus blue A B C A B 2 ZnS , H S , ZnSO , S , SO 248. 2 4 2 246. Cu A B C D E 249. CrO 2 CI 2 , Na 2CrO 4 , PbCrO 4 , iodide of Millon’s base, NH 4 CI 250. HgI 2 , KI, HgS , Hg A B C D A B C D Ritesh Classes Education should aim minds but reach hearts 36 9007102353/9831813135