PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 1 PERIODIC CLASSIFICATION OF ELEMENTS AND PERIODICITY
2008
A.Define modern periodic law. 1
B. justify the position of hydrogen in the group I-A why hydrogen is a non metal in true sense? 2
Which statement about elements in the periodic table is correct?
a. group zero elements are un-reactive metals.
B. group I-A elements form covalent chlorides.
C. the melting point of elements in group VII-A decrease with atomic number.
D. hydration energy increases significatly from left to right in a period.
2009
Hydration energies of the ions of Group IA of the periodic table are given as:
Ion
Hydration Energy
Li'
Na'
K'
-499 kj mo!-'
-390 kj mo! '
-305 kj mot-'
01
a.Define Hydration energy.
b.Why Hydration energy of K` is less than that of Na' ?02
2010
(xix)What is modern periodic law? Write briefly about blocks in the periodic table (3)
Oxidation state is the charge which an element carry in the compound,
a.On what is different in ionic and covalent compounds basis it.
01
b.On what factors does oxidation state of typical elements depend?
01
c.Transition elements show more than one oxidation state Why?
01
(i)Mark the correct statement from the following about the properties of elements in periodic table.
A.Melting point of halogens first increases and then decreases down the group
B.The ionization energy of calcium is higher than that of beryllium
C.Covalent character of metal halides increases from left to right in a periodic table
D.Lit is bigger in size than Ce
2011
(1)a.Both Sodium and Phosphorus are present in the same period of the periodic table yet
their oxides are different is nature Why?01
b.How do you justify that BeO is an amphoteric oxide? 02
(v)a .Define Hydration energy. 01
b. What factors can affect the Hydration energy? 01
c. Explain the trend of hydration energy. In group. 01
(viii)a. In what respects does hydrogen differ from halogens? 1.5
b. How does hydrogen resemble the elements of group IV-A? 1.5
(i)Upon what do the properties of an element in the periodic table depend'?
A.Atomic size
B.
Atomic mass
PAST PAPERS (XII FB)
C.Electronic configuration
SUBJECT CHEMISTRY
D
Number of protons
(v)Lanthanides and Actinides are also called
A.Normal elements
B
Transition elements
CNoble gases
D.
Inner transition elements
2012
(iii) Give reasons:
A LiCI is covalent but NaCI is ionic 1.5
B Phosphorus forms both PCl3 and PCl5 but nitrogen forms only NCl3
1.5
(vi) Oxides of relatively less electropositive metals are Amphoteric in nature.
a. ZnO is amphoteric. Justify this statement. 02
b Arrange the following oxides of Manganese in order of increasing acidic character.01
Mn2O3, MnO, Mn2O7, MnO2
(i)Which of the following oxides is most acidic?
A CO2
B Al2O3
C B 2O 3
DCl2O7
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP #2 S-BLOCK ELEMENTS
2008
sodium metal is commercially prepared by Donw’s cell.
A. are there any advantages of this method? What are the products? (2)
B. in the above method electrolysis of fused sodium chloride is carried out, why not aqueous solution
of sodium m chloride used instead? Give reasons. (1)
The element Cs is in the same group of periodic table as Na and K. which of the following is likely to be the
property of Cesium?
A. it does not conduct electricity.
B. it forms an insoluble hydroxide.
C. it reacts vigorously with hydrogen at room temperature.
d.It forms an ionic chloride of formula CsCl2.
In the commercial preparation of sodium hydroxide by the diaphragm cell the level of brine in anode
compartment is kept slightly higher so as to
a. separate the two solutions while allowing sodium ions to move towards cathode.
B. keep th direction of flow of the liquid towards cathode.
c.Keep the direction of flow of liquid towards anode.
D. prevent the oxygen gas from reacting with chlorine.
i.
2009
Solid Calcium carbonate is decomposed by heating:
a.Write an equation for the thermal decomposition of calcium carbonate. 01
b.Calcium carbonate decomposes at lower temperature than that of Barium carbcnate. Explain it. 02
(iv)Which one of the following equations represents the reaction that occurs
whenMg(NO3)2 is heated strongly?
A.
Mg(NO.)2 ->Mg(N02)2+02
B.
Mg(NO; )2 - MgO+N2O+202
C.
2Mg(NO, )2 -> 2MgO+4N02 +O,
D.
Mg (NO )2 -* MgO2 +2NO2
2010
(ii)
NaOH is prepared on large scale by the electrolysis of aqueous solution of sodium
chloride
a.What two problems are faced by a chemist during this process?
02
b.How is the first problem being solved by chemist?
01
(ii)Lithium is the first member of group I.A of the periodic table, yet it shows deviation in physical
properties from other members of its own family because of
A.Its smaller size
B
absence of d orbitals for bonding
C. Having one electron in its valence shell D. Having high charge density
2011
(ii)a.What are the advantages of Down's cell for the preparation of sodium?01
b.Why is Ca added to molten NaCl in Down's cell?
01
c.Which substances are deposited at cathode and anode in the Down's cell? 01
(ii)Which is formed when Lithium is heated in air?
A.Li2O
B.Li3,N
C.Li2O and Li3N
D Li2O2 and Li3N
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
2012
(iv) What is the action of heat on:
a. LiNO3. B NaNO3. C LiOH
1+1+1=3
Q. 4a. How is Sodium prepared electrolytically by Down's Cell? 06
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 3 GROUP IIIA AND IVA ELEMENTS
2008
Colemanitie is an ore of baric acid.
A. Describe the commercial preparation of boric acid from the above ore with equations. 1.5
B. boric acid has many different inter-convertible forms at different temperatures. Give equations to show these
changes. 1.5
Q3 carbon and silicon are present in group IV-A
a. In what respect they are different from the rest of the elements specially mention the peculiar behavior of
carbon. 2.5
b. the simplest formula for silica is SiO2. Do you expect it to be a small symmetrical and linear molecule like
CO2? If not then draw its structure and explain it. 2.5
Q3c. what are silicones? How can we synthesize them? 3
Q3d. write the properties of silicones and where are they used or have any useful applications. 5
2009
Both Silicon and Carbon are in group IV A of the periodic table.
a.What feature of their electronic structures is common to the atoms of Silicon and Carbon? 01
b. Why is SiO2 a solid while CO2 is a gas at room temperature? 02
A part of the periodic table is shown below. Using only these elements, answer the question below:
Be
B
C
Mg
Si
Al
Ge
Sn
Pb
a.Write down the formula of a chloride which is electron deficient. 01
b.Write down the formula of an oxide which is amphoteric and give its reaction
with a strong acid and a strong base separately. 02
Pure clay is obtained by weathering of rocks. Explain the process of chemical
weathering of rocks with one example. (3)
(i)Which naturally occurring substance is mainly Si02 ?
A.Haematitie
B.Lime stone
C.Cryolite
D.Quartz
2010
(iii)Carbon and silicon belong to the same group of IV.A of the periodic table.
a.Why should there be a big difference in CO, and silicon dioxide?
02
b.How is viterious silica formed from SiO, ?
01
(iii)Which of the following is the end product when Boric acid is strongly heated?
a. B2O3 b. H2B4O7 c. H3BO3 D. HBO2
2011
(iii)a.Give the names and formulae of any two different acids of boron.01
B How can we produce boron nitride from borax? 01
c.Justify that the aqueous solution of borax turns red litmus to blue. 01
2012
(v)a. How is borax prepared from colemanite? 1.5
b. Give the chemistry of Borax Bead test. 1.5
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
(ix)a. Write down the names and formulae of two non-silicate ores of aluminium. 01
B Explain why Aluminium is used in flash light photography? 01
c. Explain why Aluminium is often used to remove air bubbles from molten metals. 01
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 4 GROUP VA AND VIA ELEMENTS
There are two important oxy acids of nitrogen.
A. write down the electronic structure of nitrous acid. 0.5
B. explain the manufacturing process of nitric acid byBirlkland and Eddye’s process with diagram and
equations. 2.5
2008
i.
Choose the correct products for the reaction between concentrated nitric acid and tin:
a.
Sn + HNO3
Sn(NO3)2 + NH4NO3 + H2O
B.
Sn + HNO3
H2SnO3 + NO2 + H2O
C.
Sn + HNO3
Sn(NO3 )2+ NO2 + H2O
D.
Sn + HNO3
H2SnO3 + NO2 + H2O
2009
Nitrous acid behaves as an oxidizing as well as a reducing agent.
a.Write an equation for the reaction which confirms that it is reducing agent.(2)
b.Define Reduction.(1)
(v)The brown gas formed, when metal reduces HNO3
A.NO2
B.
C.N2O ,
D.
is:
NO
N/O5
(xiii)Oxidation of NO in air produces:
A.N2O
B .N2O4:
C.N2O3
D, .N2O5
2010
(iv)
Nitrogen forms two oxyacids.
a.Draw electronic structures of these two acids and write their names.
01
b.Zinc combines differently with one of the above mentioned acids depending
upon the concentration of an acid. Write equations for the reactions between
Zinc and that acid when:
(i)Acid is very dilute
02
(ii)
Acid is very concentrated
Q. 3Nitrogen and phosphorous belong to the group V A of the periodic table
a.Write down the names and draw molecular structure of any two allotropic forms of phosphorous
What major properties are shown by these two allotropes Which is the most stable one 07
b.Phosphoric acid converts itself into other acids on heating Write down the names of products
and equations of this conversion.(3)
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
c. P2O5 is strong dehydrating agent'. Prove this statement giving examples
03
(iv)Sulphur forms three different compounds with chlorine. The type of hybridization shown by
sulphur in S('/,, is
A.sp3
B. sp3d
C. sp2
D. sp3d2
2011
Q. 5a. How does Sulphur differ from Oxygen? 02
b. Show with the help of flow sheet diagram how Sulphur is converted into Sulphuric acid. 05
c. Sulphuric acid is said to act as an acid, an oxidizing agent and dehydrating agent. Describe two
reactions in each case to illustrate the truth of this statement.
06
(iii)Laughing gas is chemically
A. NO
B N2O
C. NO2
D N 2O 4
2012
(ii)a Give the electronic structure of nitrous acid. 01
B Nitrous acid decolorizes bromine water. Explain this behaviour with the help of chemical equation.
01
C Write a balanced chemical equation to show, how nitrous acid oxidizes HI
(viii) Give complete and balanced chemical equations for the reaction between
A Zinc with conc. HNO3
01
b. Copper with hot conc. H2SO4 01
C NaBr with conc. H2SO4
01
01
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 5 THE HALOGENS AND NOBLE GASES
2008
Compounds of halogens have many commercial uses.
A. the term available chlorine is often used for the bleaching powder. Explain the tem while giving an
equation. 1
B. hydrogen fluoride occurs in different state than other hydrogen halides at room temperature. Explain
the reason and also justify the statement that its viscosity is less than that of water 1
C. write down the commercial uses of bromine. 1
Experiment Halogen added
NaX
1
X2
….
2
Y2
No reaction
3
Z2
No reaction
What were the halogens added?
X
Y
A Bromine Chlorine
B Bromine Iodine
C Chlorine Iodine
D Chlorine Bromine
Nay
Y2 displayed
…
Y2 displayed
NaZ
Z2 displayed
No reaction
….
Z
Iodine
Chlorine
Bromine
Iodine
2009
Standard electrode potential measures oxidizing power
Standard Reduction Potential E˚(v)
F2
Cl2
2.84 1.36
Br2
1.07
I2
0.54
Why the oxidizing power of F, is higher?(1)
Upon which factors, does the oxidizing power of halogens depend?(2)
(ii)The following acids have been arranged in the order of decreasing acid
strength. Identify the correct order:
I
II
11
HOBr
HOI
HOC!
A.
111>1I>I
B.
I>I//>11
C.
1>1I>111
D.
11>I>111
2010
(v)
Keeping in view the systematic rules for the nomenclature of oxyacids:
a.Name the following
HClO, HClO2, HClO3, HClO4
b.What is iodized salt? Why is it used in diet?
02
01
2011
2012
(vii)a.Write down the names and formulae of two oxyacids of chlorine having +3 and +7 oxidation
states.
02
b. Why are the oxyacids of chlorine stronger than the corresponding oxyacids of bromine and
PAST PAPERS (XII FB)
iodine?
SUBJECT CHEMISTRY
01
iv)Salts of HClO4 are known as
A. Hypochlorite
C Chlorite
B. Perchlorate
D.Chlorate
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 6 TRANSITION ELEMENTS
2008
KMnO4 is a purple coloured compound and Ti gives a solution [Ti(H2O)6]+3 ions, which looks violet in
colour. Explain the reason behind the colour development of these compounds.1.5
B. name the compound [CO(NH3)6]Cl3 and draw its structure and also name the type of hybridization
taking place in the complex.0.5+0.5+0.5
Vi
Steel can be protected from rusting by spraying it with zinc. Zn is used because:
a.
b.
c.
d.
Zn has a high melting point so it does not corrode easily
Zn does not react with acidic exhaust fumes.
Zn forms a stable compound with iron.
Zn is higher in reactivity series than iron.
2009
Give IUPAC Name. K2[PtCl6]
Iron and Chromium are Transition elements.
a.(i)Write two properties of iron or its compounds that typify it as a transition element.02
(ii)What is the difference between wrought iron and steel? 02
(iii)How is iron protected from rusting by the process of Galvanizing? 03
b.(i)Draw the structure of Dichromate Cr2O7-2 ion. 02
(ii)What is chromyl chloride test? Write its equation for NaCl. 02
(iii)How is potassium dichromate prepared? 02
(iii)Pyrolusite is mineral of:
A.Copper
C.Iron
B.
D.
Chromium
Manganese
2010
(vi)
a.
What is Paramagnetism?
02
b.
What is the cause of Paramagnetism?
01
2011
(vi)a How does K.Cr,0 act as an oxidizing agent? Give one equation. 01
b. What is Chromyl chloride test? 01
C. How does the acidic medium develop an equilibrium between chromate and dichromate ion? 01
(x) Name the following co-ordination compounds.03
a. K4[Fe(CN)6] b. [CoBr(NH3)3]SO4 c. [Cr(NO2)3(NH3)3]
2012
(i)a. What are Complexes?
01
b. Write the systematic name of the complex K 3 [Fe(CN)6]
01
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
C, Why Fe+3 ions do not exist in solution? 01
Q4b. Slow and continuous eating away of a metal by atmospheric reagents is called corrosion.
(i) How does the electrochemical theory explain the phenomenon of corrosion?
(ii)Why is galvanizing superior to Tin Plating? 03
04
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 7 FUNDAMENTAL PRINCIPLES OF ORGANIC CHEMISTRY
2008
Only 20% gasoline is obtained by the fractional distillation of petroleum due to energy crisis it is required in
large amount now a days.
A. name the process and also give equations by which its high demand is met. 1
B. what is the standard of finding about the quality of fuel? Define it. 1
C. how the quality of a fuel can be improved? Name the procedure and give equations for the process. 1
vii. Carbocyclic compounds are further divided into:
a. acyclic, alicyclic b. acyclic, cyclic c. aromatic, non aromatic d. aromatic, alicyclic
xvi. Which formula of the following functional groups is called as imino group?
A. –NH2
b. C=NH .
c.
–CΞN
d. –CO-NH2
2009
Some of the larger Hydrocarbons in crude oil are subject to the process of cracking.
a.Explain the term cracking by one example.02
b.Why 's cracking a commercially important process?01
There are different structural isomers of formula C4H,OH
A Draw the structures of the four Alcohols of formula ( H,01/ (2)
B Classify these isomers as primary, secondary or tertiary(1)
2010
(vii)
The quality of gasoline is improved by the process called Reforming.
a.
What happens when the spark plug fire ignites low quality gasoline in the
engine of automobile?
01
b.
How is the octane number of n-octane improved?
01
C.
Write the formula'of T.E.L.
01
(vii)In isomerism, compounds have same molecular formula, but different structures.
The possible isomers formed by pentane are
A.Five
B.
Four
C.Three
D.
Two
2011
Which of the following is not a cyclic compound? A. furan b. thiophene c. pyridine d. aniline
2012
Q3b. What is Orbital hybridization? Explain.sp2 hybridization in ethene. 04
(viii)Which of the following pairs of substances is Isomers?
A.Ethyl benzene and 3, 3-Dimethyl pentane
BCyclopentanol and 2 - Pentanone
C.2 - Pentanol and 3 - Methyl butanone
D Propyl ethanoate and Methyl propanoate
(xv)Which of the following contains oxygen as hetero atom?
A.Furan
B.
CThiophene
D
Pyrrole
Pyridine
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 8 ALIPHATIC HYDROCARBONS
2008
An organic compound has the molecular formula C4H8 which on ozonolysis gave three different products.
A. write equations for the ozonolysis. 2
B.Name the type of isomerism present in the compound C4H8. 1
Q5. Hydrogenation is a process used in the laboratory as well as in industry.
a. Define the following terms. i. catalytic hydrogenation ii. Heat of hydrogenation. 2
Q5b. The catalyst employed in the above process is Raney Nickel. How is it prepared? 1
Q5d. Write equation for the following reactions with their specific catalysts and conditions.
i. 3 methyl-1-buteneinto iso pentane ii. 2 butyne into cis-butene
iv. 2 butyne into trans butene.
viii. Synthetic rubber is obtained when:
a. acetylene is passed in the amonical solution of cuprous chloride.
B. acetylene is passed in the acidic solution of cuprous chloride and ammonium chloride and then
concentrated HCl is added.
C. acetylene is passed through a copper tube at 300C
d. acetylene is reacted with HCN in the ammonical solution of cuprous chloride at higher temperature.
xvii. An organic compound exhibits the following properties
a. it does not undergo polymerization reaction b. It does not undergo substitution reaction through free redical
mechanism
c. it undergoes oxidation and colour of KNnO4 is discharged
From the study of the above properties what conclusion do you arrive about its identity?
The compound is a. an alkane b. an alkene. C. an alkyne d. an aromatic compound.
2009
Name the following compounds according to IUPAC
(CH3)2C= CH2
In Ethyne and other terminal alkynes, H-atom attached to the triply bonded carbon
is slightly acidic.
a. Why 1-alkynes or Ethyne show acidic behaviour?(2)
b.Write a reaction to show the acidic behaviour of Ethyne.(1)
2010
(viii)
Halogenation is believed to proceed through free radical mechanism in alkanes
a
Write the names of steps involved in this process with examples.
01
b.
Complete the conversion of ('11, -CY to CO, during one of the above steps in detail.
02
Q5b.Write structural formula of the following compounds and name them according to I.U.P.A C
system of nomenclature. 02
(i)Chloroprene
(ii)Mustard gas
2011
(iv)Give mechanism of Kolbe's electro synthesis of Ethene. 03
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
(xi)a 1-Butene does not show geometrical isomerism but 2-butene does. Justify it. 01
b.Why is restricted rotation necessary to show the geometrical isomerism? 01
c. Write all possible isomers of C2H2Br2 01
(xii)a.Define Markownikov's rule. 1. 5
b.Complete the following reaction CH 2 = CH-CH3 + HOCl
1.5
(vii)Preparation of vegetable ghee involves
AHalogenation
B.
Hydrogenation
C.Hydroxylation
D
Dehydrogenation
(x)When an unsymmetrical olefin like(CH3)2CHCH=CH2 is hydrated with dil. II2SO4 the major
product is
A.3-Methy-1 -butanol
B
1-Methl 2-butanol
C.3-Methyl -2-butanol
D.
2-Methyl 2-butanol
Geometric isomerism will be exhibited by
A.
1-pentene
B.
3-Methyl-l -butene
C.
2-pentene
D.
All of these
2012
(x)a. What is the effect of branching on the boiling points of Alkanes? 01
B What are the three different alkenes that yield 2 - methyl butane, when they are hydrogenated in
the presence of a catalyst?
02
(xii) what happens when:
a. 2 - Methyl 2 - butene is ozonolysed, followed by Zn / H 20 treatment 1.5
b. Acetaldehyde is treated with NaCN / HCI and the product is followed by
acid hydrolysis. 1.5
(xix)Differentiate between the following pairs of compounds? Also give your observations with the
help of only one valid chemical test in each case.
a. 1- Butyne and 2 - Butyne
(1)
(xvi)Kolbe's electrolysis of sodium n-butyrate CH3CH2CH2COONa gives
AC8H16
B.C6H14
CC8H18
DC6H12
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 9 AROMATIC HYDROCARBONS
2008
What is halogenonium ion? How is it produced? Describe the mechanism when this specie attacks on benzene
ring. 1.5
B. What products are obtained by the nitration of bromobenzene? State the reason behind the formation of
these products. 1.5
Q5c. Explain the following statement “ the extent of stability of benzene can be measured by comparing it with
hypothetical compound 1,3,5 cyclohexatriene. This can be done by estimating their heats of hydrogenation. 4
2009
The carbon-carbon bond length in Benzene is different from that in Ethene.
a.Which compound contains the longer bond?(1)
b.Give reason for your answer.(2)
Aromatic compounds undergo Electrophilic Substitution reactions.
aExplain why Nitration of Toluene is easier than that of Benzene(1)
bHow would you convert Toluene into Trinitrotoluene (2)
2010
(xviii)Benzene is an extraordinary stable molecule. Justify the truth with the help of example 03
Q. 5a.Define Reasonance Draw all the possible resonating structures shown by a benzene What
structure would you suggest best for representing benzene?
06
Q5bWrite structural formula of the following compounds and name them according to I.U.P.A C
system of nomenclature. T.N T (1)
(ix)Which of the following compounds will be sulphonated most readily?
A.Toluene
B
Benzene
C.Aniline
D.
Chlorobenzene
(xvii)Which of the
is an electrophile?
2011
(xiii)a.How can benzene be converted into acetophenone? 01
2012
(xvi) Write the structural formula of Acetophenone
(xviii) Predict the product:
C H CH CH 
? (1.5)
KMnO4
6
5
2
3
[O]
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 10 ALKYL HALIDES
2008
Tertiary alkyl halides generally follow E1 mechanism, explain with the help of equations. 1
B What different products are obtained if tertiary alkyl halide undergo SN1 mechanism instead? 1.5
C. what conditions are required for the SN1 mechanism? 0.5
ix. R-Mg-X + Y
a. carbon dioxide
A compound
b. aldehyde
H3O+
c. ketone
what compound is Y ?
d. ethylene epoxide
2009
The compound 2-Bromo-2-m ethyl butane (CH, - ('H2 -- C(C/l, ). Br) reacts with aqueous Potassium
hydroxide solution to produce 2-Methyl-2-Butanol
(CH, -CH, -C(CH,OH)
a.Give the mechanism (2)
b.Identify the rate determining step.(1)
2010
(x)The rate of SN1 mechanism depends upon
A.The concentration of nucleophile B. The concentration of substrate
C. The concentration of substrate and nucleophile D.The concentration of catalyst
(xii)Which of the following reagents will react with both aldehydes and ketones"
A.Grignards reagent
B
Tollen's reagent
C.Benedict's reagent
D
Fehling's reagent
2011
(xiv)a. How does nature of alkyl group change when alkyl halide is converted into Grignard's
reagent? 01
b. Why is the dry ether necessary for the preparation of Grignard's reagent? 01
c. How does the primary alcohol produce when ethylene oxide reacts with Grignard's reagent? 01
2012
(xvii) How will you convert: Ethyl bromide to propionic acid 1.5
Q. 3The reactions in which halogen atom of an alkyl halide is replaced by a Nucleophile are called S N`
reactions
a. Compare in tabular form, the SN1 and SN2 reactions. 06
(ix)Chlorobenzene reacts with 'Mg' in dry ether to give a compound 'X', which further reacts
withethanol to give
A.Benzene
B
Phenol
C.Ethyl benzene
D.
Phenyl ether
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 11 ALCOHOLS PHENOLS AND ETHERS
2008
A. Describe the commercial preparation of methanol along with the labeled diagram. 1.5
B. arrange the following compounds in order of their increasing acid strength, while giving reasons.
C6H5COOH,C6H5OH,C2H5OH,H2O 1.5
Q4c. Write the structural formula of following compounds and name them according to IUPAC system i. Didisoporpyl ether
1
x. ROH + RCOOH H2SO4
RCOOR + H2O the order of reactivity of alcohol in the above case is
a. ter-alcohol>sec-alcohol>primaryt alcohol
b. primary alcohol>sec-alcohol>ter-alcohol
c. CH3OH>primary alcohol>ter-alcohol>sec-alcohol
d. sec-alcohol>primary alcohol>ter-alcohol
2009
Ethers contain-C- O - C - functional group.
a.Describe preparation of Ethers by Williamsons Synthesis.(2)
b.Why are Ethers slightly soluble in water?(1)
(viii)Rectified spirit contains alcohol about:
A.80%
B.
C.95%
D.
90%
85%
2010
(xii)Ethanol is prepared on industrial scale world over
a.Name the process, temperature and enzymes used for the above process
when ethanol is prepared from the residue of sugar with equations (2)
b.Only 12% alcohol can be prepared by this process Why(1)
2011
(xvii)a. What is Absolute alcohol and Rectified alcohol? 01
b. Absolute alcohol can not be prepared by fermentation process. Why? 01
c. What is meant by denaturing of alcohol? 01
(vi)What is the name of the reaction when C 2H5ONa+C2H51gives an ether?
A.Hofmann's reaction
B.
Williamson's reaction
C.Kolbe's synthesis
D
Wurtz's reaction
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
(viii)An organic compound is capable of reacting with sodium and is capable of being oxidised to a
carboxylic acid. The compound contains only carbon, hydrogen and oxygen. This organic ompound
my be
A.Alcohol
B
Aldehyde
C.Carbohydrate
D.
Ether
2012
(xi) Explain why
a. Hydroxyl group (-OH) in phenol is ortho-para directing. 1.5
b. Phenol undergoes Nitration faster than nitrobenzene. 1.5
(xiii) A secondary Alcohol A C3H8O reacted with thionyl chloride to give compound 'B' C 3H7CI.
Compound 'B' reacted with Benzene in the presence of A1Cl3 to give compound 'C' C9H12 Identify
'A', 'B' and 'C'.
(xviii) Predict the product:
03
(CH ) COH ? (1.5)
Conc . H 2 SO4 heat
3
3
(xix)Differentiate between the following pairs of compounds? Also give your observations with the
help of only one valid chemical test in each case.
Methanol and Ethanol
1
(x)When ethyl iodide reacts with sodium methoxide, it gives
A.Methyl ethyl ether
B
Diethyl ether
C.Ethanol
D. Sodium ethoxide
(xiv)Which of the following primary alcohols will give lodoform test?
A.Ethanol
B
Methanol
C.1- Propanol
D
2 - Propanol
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 12 ALDEHYDES AND KETONES
2008
Carbonyl compounds are reduced to their corresponding alcohols by NaBH4 in ether solution. One of such
compounds is reduced to an alcohol which cannot be dehydrated intra-molecularly. A. identify the structure of
the compound. 0.5
B. give equation and mechanism of the reduction. 1
C. carbonyl compounds can be oxidized. Give two different oxidation reactions. Used to identify an aldehyde
from a ketone. Describe and explain the changes you observe in these reactions1.5
Suggest the mechanism for the conversion of acetaldehyde into lactic acid. 3
Q4c. Write the structural formula of following compounds and name them according to IUPAC system i. Acetal
1
xi. butanone when oxidized in the presence of acidified potassium dichromate gives the following products:
a. CH3COOH + CH3COOH B. HCOOH + CH3CH2COOH
C. CH3COCH3 + HCOOH
D. CH3 CH2 CH2COOH only.
2009
Q.4a Consider the fcllowing series of reactions involving Ethanal, then answer the
questions which follow:
(i)Draw the structural formula of the compound 'Y' and 'Z'.02
(ii)Describe the appearance of the compound X. Give its name. Give outline of the mechanism for the
reaction of Ethanal with 2, 4-DNPH to produce compound X. 05
(iii) Give a chemical test by which you could distinguish between Ethanal and
Propanone.02
(vii)Which compound reacts with its own oxidation product to give a
sweet-smelling liquid?
A.Propanal
B.
1
- Propanol
D.
Propane
C.Propanoic acid
(xiv)What arethe geometries of the carbonyl carbon (C =O) in acetaldehyde
and then in the Acetal?
A.Trigonal Pyramid in acetaldehyde and Trigonal Pyramid in acetal
B.Trigonal planar in acetaldehyde and Tetrahedral in acetal
C.Trigonal Pyramid in acetaldehyde and Tetrahedral in acetal
D.Trigonal Planar in acetaldehyde and Trigonal Pyramid in acetal
2010
(xiii)The reactions in which two molecules combine to form new compounds with or with or
without elimination of a small molecule is called Condensation
a.What type of condensation will be shown by the following.
a. CH3CHO B. C6H5CHO (1)
b.Write chemical equation along with mechanism for the conversion of CH3CHO
into products.02
Q4b.Describe the reactions between carbonyl compounds with the following compounds (i) 2.4
DNPH ii. NH2-NH2
Also mention general mechanism for their conversion
06
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
Q5c.How will you bring about the following conversions?
02
(i)Propanone into 2-Propanol
2011
(xv)a. Why the aldehydes with no a -hydrogen give Cannizzaro's reaction? 1.5
b. Distinguish between benzaldehyde and acetaldehyde. 1.5
(xviii)Show with the help of mechanism how acetaldehyde in the presence of strong base gives
crotonaldehyde.
03
(ix)Propanone is a ketone which could be prepared by the action of potassium dichromate
K2Cr2O7 on
A.1-propanol
B
2-propanol
C.Propene
D.
Propanoic acid
Which compound will give a positive Tollen's test?
A.
Pentanoic acid
B.
2-Pentanone
C.
Pentanal
D.
3-pentanone
(xi)Acetone undergoes reduction with zinc amalgam in HCl to form propane. This is known as
A.Clemmensen reduction
B
Wolf Kishner reduction
D.
Hydrogenation
C.Aldo] condensation
2012
(xiv)a. Write the formula of 2,4 - Dinitrophenyl hydrazine and Semicarbazide 01
b. Give the mechanism of the reaction between formaldehyde and hydrazine. 02
(xix)Differentiate between the following pairs of compounds? Also give your observations with the
help of only one valid chemical test in each case.
Aldehydes and Ketones
01
Q3c. What is Cannizzaro's reaction? Write its mechanism 03
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 13 CARBOXYLIC ACIDS
2008
What trend of solubility and boiling points are followed in the homologous series of carboxylic acids? 3
Q4c. Write the structural formula of following compounds and name them according to IUPAC system
i.phthalic acid 1
xii. Which set of following steps give exact sequence of processes that are involved I the conversion of
acetylene into acetic acid.?
A. hydration, oxidation, rearrangement
c. hydration, rearrangement, oxidation
b. rearrangement, hydration, oxidation
d. oxidation ,hydration, rearrangement
2009
Name the following compounds according to IUPAC system
HO-CH-COOH
HO-CH-COOH
Acetic acid is a component of vinegar
a. How is Acetic acid manufactured from Acetylene?
b. What is glacial acetic acid?
2010
xiv)Esters formed carboxylic acids give different flavours What type of
flavours is given by Amylacetate, Isobutyl formate and Benzylacetate
Q5c.How will you bring about the following conversions? 02
(i)Ethanol into Ethanoic acid
2011
(xvi)a. How is acetic acid prepared from alkyl nitriles? 01
b. Give the mechanism for the reaction of acetic acid with SOCl 2 02
2012
(xvii) How will you convert: Acetic acid to acetaldehyde 1.5
(xvii)Acetic acid undergoes reduction with LiAlH4, to give
03
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
A.Ethanol
B.
Ethane
C.Ethanal
D
Ethyne
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 14 MACRO MOLECULES
2008
Polymers have an important utility in our daily life
a. explain the term copolymer 1
b. base d on the thermal property of a polymer, what type is epoxy resin 0.5?
C. how is a peptide linkage formed? What type of polymerization takes place in this case? 1.5
Nucleic acids have been discovered in this century.
A. define replication 0.5
b. what are the differences between the two types of nucleic acids DNA and RNA? 1.5
C. write the structure of cellulose naming the type of linkage present in it. 1
Q5d. Write equation for the following reactions with their specific catalysts and conditions.
i. Hardening of oil in industry
2009
DNA carries the genetic code in living organisms and consists of a double helix
A How are the strands of the double helix held together?(1)
b.How does DNA differ from RNA?(2)
Nylon- 6, 6, the synthetic polymer is used to blend with wool (protein) in clothes.
01
(i)Name the functional group common to both Nylon-6, 6 and protein.
(ii)Draw repeat unit of Nylon- 6, 6, from its monomers. 03
(x)Glucose and Fructose are.
A.Metamers
C.Functional isomers
2010
B
D
Chain isomers
Position isomers
(xv)Polymers have an mportant utility in our daily life
a. How is the molecular mass of the polymers determined? Give an example 01
b. What type of polymerization is shown by the mutual reaction of two functional groups? Give
example
02
(xvi)Proteins are complicated molecules of living organisms How many levels of structural
organizations are shown by proteins? Explain by drawing structures if any
03
Q. 4Lipids are essential for the growth of animals
a.(i)What are Lipids? Write their main characteristics 03
(ii)How are these lipids classified' Draw the structure and composition of fats and oils 02.02
2011
Q. 3a. What are amino acids? Give one example each of acidic, basic and neutral amino acids. 04
b. How are carboxylic acids and aldehydes converted into α-amino acids?
c. How can a -amino acid be converted into a -hydroxy acids? 02
04
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
d. What are Zwitter ion and peptide linkage? 02
e. How are a -amino acids tested? 01
Amino acids are covalently bonded to each other through
A.
Hydrogen bonding
B.
Disulfide bridges
C.
Peptide bonds
D.
None of these
2012
(xv) Starch is a mixture of Amylose and amylopectin.
a. Point out the structural difference between amylose and amylopectin.02
b.How they can be differentiated chemically? 01
(xvi)Write the structural formula of Acrylonitrile, adipic acid
Q. 5a. What are Lipids? Describe the properties of lipids under the following heads. 04
(i) Sponification (ii) Hardening of oils
(xii)Which of the following is an addition polymer?
B.
A.Polystyrene
C.
Epoxyresins
(xiii)Which of the following is NOT present in RNA?
A.Uracil
B.
C.Thymine
D
Polyester
D.
Bakellite
Phosphate
Ribose
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 15 COMMON CHEMICAL INDUSTRIES IN PAKISTAN
2008
Paper and cement industries are the most demanded ones now a days.
A. explain the process of the digestion of pulp. 1.5
B. the use of cement in the construction of building is based on its property of setting to a hardness. Describe
the reactions involved in the setting of cement in first 24 hours. 1.5
How fertilizers are classified and what role each type of fertilizer has? 3
Q4a.Define the term micro-nutrient and macro-nutrients. 2
Q4b. Describe the manufacture of urea giving flow sheet diagram. 5
Q4d. what are pesticides? What health problems can be caused by them if they are sued? 3
XIV. Which of the fertilizer does not make the soil acidic?
A. ammonium nitrate b. calcium cynamide
c. potassium nitrate
2009
d. urea
Cement is a very important building material.
a.Define cement.
b.What is a Slurry?
(xii)Which process is used in chemical pulping for the production of paper pulps'?
A.Kraft process
B.Sulphite process
C.Neutral sulphite semi-chemical process
D.All of these
2010
(xv)Which of the following is non-calcarious?
A.Lime
B
Lime stone
C.Sea shells
D
NH4OH
2011
(vii)a. What is Rotary kiln?
01
B Give different zones in the rotary kiln and their temperature ranges. 01
c. What is the final product of rotary kiln?
01
Which sequence of steps is CORRECT for the manufacture of cement?
A.
Mixing, heating, grinding, crushing
B.
Crushing, heating, mixing, grinding
C.
Crushing, mixing, heating, grinding
D.
Crushing, grinding, mixing, heating
2012
Q5c. Describe the different steps involved in the manufacture of Urea. 05
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY
CHAP # 16 ENVIRONMENTAL CHEMISTRY
2008
A. why chlorination of water is a frequently used method? Which compound is used to generate chlorine and
why? In what always chlorination is not a very effective method? 2
B. Define the term leachate. What are its components especially the micro pollutants? 1
xv.Which property in not shown by the pollutant peroxy acetyl nitrate?
A. a main component of photo chemical smog.
B. it is an eye irritant.
C. it is toxic to plants.
D. it is harmful for fish as it clogs the gills causing suffocation.
2009
The concentration of ozone in the stratosphere is being depleted through various
chemical reactions worldwide
a.What is meant by "ozone hole"(1)
b.Write chemical equations for the reactions by which CFCs are removing
in the stratosphere. (2)
(xi)In whichpair do both pollutants cause damage to buildings?
A.Nitrogen dioxide and Sulphur dioxide
B.Carbon monoxide and Lead compounds
C.Nitrogen dioxide and Lead compounds
D.Carbon monoxide and Lead compounds
2010
(xvii)What is Smog?
which pollutants are the main cause of smog? Explain. (1+2=3)
(xvi)Which of the following disinfects drinking water?
A. NH4Cl
B.HCl
C.HOCl
D NH4OH
2011
(ix)a What is Smog? Give its sources.01
01
b. What is Photochemical smog?
c. What are the conditions for the formation of smog? 01
Q. 4a.Discuss briefly the various sources which contaminate water 06
b.Discuss briefly the various stages of water treatment. 03
c. What are the harmful effects of chlorination of water? 02
d. How COD is measured? 02
Which of the following is NOT an affect of the acid rain?
A.
It increases the percentage of CO2 in the atmosphere
B.
It leaches metals like aluminum, mercury and lead from soil
C.
It damages the buildings
D.
It decreases the pH of natural rain
2012
Q5b. Quality of water is determined in terms of certain factors. Explain: 04
(i)Bio - Chemical Oxygen Demand (BOD) (ii)
Chemical Oxygen Demand (COD)
PAST PAPERS (XII FB)
SUBJECT CHEMISTRY