AIEEE 2007 Practice Test 2 - Test duration is 2 hours. Instructions 1. All questions are compulsory. 2. Every question carries 3 marks. 3. Do not write anything on answer sheet except in the marked area. 4. Every incorrect answer carries -1(negative) mark 5. The paper is of 2 hours duration Syllabus Physics - Heat, SHM and waves Chemistry - Electrochemistry , Hydrocarbons, Mathematics - Probability, Trigonometric equations and inverse trigonometric functions Q1. Two holes of unequal diameters d1 and d2 (d1 > d2) are cut in a metal sheet. If the sheet is heated, (a) both d1 and d2 will decrease (b) both d1 and d2 will increase (c) d1 will increase, d2 will decrease (d) d1 will decrease, d2 will increase Q2. In the previous question, the distance between the holes will (a) increase (b) decrease. (c) remain constant (d) may either increase or decrease depending on the positions of the holes on the sheet and on the Q3. A metal wire of length l and area of cross-section A is fixed between rigid supports at negligible cooled, the tension in the wire will be (a) proportional to l (b) inversely proportional to l (c) independent of l (d) independent of A ratio d1/d2 tension. If this is Q4. Two metal rods of the same length and area of cross-section are fixed end to end between rigid supports. The material of the rods have Yong modulii Y1 and Y2, and coefficients of linear expansion a1 and a2. The junction between the rods does not shift if the rods are cooled. (a) Y1a1 = Y2a2 (b) Y1a2 = Y2a1 (c) Y1a12 = Y2a22 (d) Y12a1 = Y22a2 Q5. Three rods of equal length are joined to form an equilateral triangle ABC. D is the midpoint of AB. The coefficient of linear expansion is a1 for AB, and a2 for AC and BC. If the distance DC remains constant for small changes in temperature, (a) a1 = a2 (b) a1 = 2a2 (c) a1 = 4a2 (d) a1 = Q6. a2 When the temperature of a body increases from t to t + Dt, its moment of inertia increases from I to I coefficient of linear expansion of the body is a. The ratio + DI. The is equal to (a) (b) (c) aDt (d) 2aDt Q7. A horizontal tube, open at both ends, contains a column of liquid. The length of this liquid column does not change with temperature. Let g = coefficient of volume expansion of the liquid and a = coefficient of linear expansion of the material of the tube. (a) g = a (b) g = 2a (c) g = 3a (d) g = 0 Q8. In a vertical U-tube containing a liquid, the two arms are maintained at different temperatures, t1 and t2. The liquid columns in the two arms have height l1 and l2 respectively. The coefficient of volume expansion of the liquid is equal to (a) (b) (c) (d) Q9. A solid whose volume does not change with temperature floats in a liquid. For two different temperatures t1 and t2 of the liquid, fractions f1 and f2 of the volume of the solid remain submerged in the liquid. The coefficient of volume expansion of the liquid is equal to (a) (b) (c) (d) Q10. A solid with coefficient of linear expansion a just float in a liquid whose coefficient of volume system is heated, the solid will (a) sink in all cases (b) continue to float in all cases expansion is g. If the (c) sink if g > 3a (d) sink if g < 3a Q11. A gas at absolute temperature 300 K has pressure = 4 x 10–1 N/m2. Boltzmann constant = k = 1.38 x 10–23 J/K. The number of molecules per cm3 is of the order of (a) 100 (b) 105 (c) 108 (d) 1011 Q12. The root-mean-square (rms) speed of oxygen molecules (O2) at a certain absolute temperature is v. temperature is doubled and the oxygen gas dissociates into atomic oxygen, the rms speed would be (a) v If the (b) (c) 2 v (d) Q13. The average translational kinetic energy of O2 (molar mass 32) at a particular temperature is 0.048 average translational kinetic energy of N2 (molar mass 28) molecules in eV at the same temperature is (a) 0.0015 (b) 0.003 (c) 0.048 (d) 0.768 eV. The Q14. gas is A gas has volume V and pressure p. The total translational kinetic energy of all the molecules of the (a) pV only if the gas is monatomic (b) pV only if the gas is diatomic (c) > (d) pV only if the gas is diatomic pV in all cases Q15. A closed vessel is maintained at a constant temperature. It is first evacuated and then vapour is continuously. The pressure of the vapour in the vessel (a) increases continuously (b) first increases and then remains constant (c) first increases and then decreases (d) none of the above injected into it Q16. When an air bubble rises from the bottom to the surface of a lake, its radius becomes double. Find the depth of the lake, given that the atmospheric pressure is equal to the pressure due to a column of water 10 m high. Assume constant temperature and disregard surface tension (a) 30 m (b) 40 m (c) 70 m (d) 80 m Q17. Two containers of equal volume contain the same gas at pressures p1 and p2 and absolute temperatures T1 and T2 respectively. On joining the vessels, the gas reaches a common pressure p and a common temperature T. The ratio p/T is equal to (a) (b) (c) (d) Q18. Two identical containers joined by a small pipe initially contain the same gas at pressure p0 and absolute temperature T0. One container is now maintained at the same temperature while the other is heated to 2T0. The common pressure of the gases will be (a) (b) (c) (d) 2p0 Q19. In the pressure question, let V0 be the volume of each container. All other details remain the same. moles of gas in the container at temperature 2T0 will be The number of (a) (b) (c) (d) Q20. A horizontal cylinder has two sections of unequal cross-sections in which two pistons can move are joined by a string. Some gas is trapped between the pistons. If this gas is heated, the pistons will freely. The pistons (a) mole to the left (b) move to the right (c) remain stationary (d) either (a) or (b) depending on the initial pressure of the gas Q21 A particle of mass 1 kg is moving in SHM with an amplitude 0.02 and a frequency of 60 Hz. The acting on the particle is (a) 144 p2 (b) 188 p2 (c) 288 p2 (d) None of these Q22 at time An instantaneous displacement of a simple harmonic oscillator is x = A cos (wt + p/4). Its speed will maximum force be maximum (a) p/4 w (b) p/2w (c) p/w (d) 2 p/w Q23 Velocity of sound waves in air is 330 m/s. For a particular sound wave in air, a path difference of 40 equivalent to phase difference of 1.6 p. The frequency of this wave (a) 165 Hz (b) 150 Hz (c) 660 Hz (d) 330 Hz Q24 The velocity of sound in air is 330 m/s. The rms velocity of air molecules (g = 1.4) is approximately cm. is equal to (a) 400 m/s (b) 471.4 m/s (c) 231 m/s (d) 462 m/s Q25 Sound waves of length l traveling with velocity v in a medium enter into another medium in which their v. The wavelength in 2nd medium is (a) 4 l (b) l (c) l/4 (d) 16 l Q26 The velocity of sound in a container of air at − 73 °C is 300 m/s. Its temp. of container were raised would be the velocity of sound ? (a) 300 m/s (b) 300 (c) 300 / (d) 600 m/s velocity is 4 to 127 °C. What m/s m/s Q27 If the intensities of two interfering waves be I1 and I2, the contrast between maximum and minimum maximum, when (a) I1 >> I2 (b) I1 << I2 (c) I1 = I2 (d) Either I1 or I2 is zero Q28 Two periodic waves of intensities I1 and I2 pass through a region at the same time in the same of the maximum and minimum intensities is (a) 2(I1 + I2) (b) I1 + I2 intensity is direction. The sum (c) (d) Q29 If two tuning forks A and B are sounded together, they produce 4 beats per sec. A is then slightly and same no. of beats / sec are produced again. If frequency of A is 256, the frequency of B would be (a) 250 (b) 262 (c) 252 (d) 260 Q30 If the ratio of maximum to minimum intensity in beats is 49, then the ratio of amplitudes of two trains is (a) 7 : 1 (b) 4 : 3 (c) 49 : 1 (d) 16 : 9 Q31 A uniform wire of length 20 m and weighing 5 kg hangs vertically. If g = 10 m/s2, then the speed of waves in the middle of the wire is (a) 10 m/s loaded with wax progressive wave transverse (b) 10 m/s& (c) 4 m/s (d) 0 Q32 If there are six loops for 1 m length in transverse mode of Melde’s experiment., the no. of loops in mode under otherwise identical conditions would be (a) 3 (b) 6 (c) 12 (d) 8 Q33 The fundamental frequency of an open organ pipe is 300 hz. The first overtone of this pipe has same first overtone of a closed pipe. If speed of sound is 330 m/s, then the length of closed organ pipe is longitudinal frequency as (a) 41 cm (b) 37 cm (c) 31 cm (d) 80 cm Q34 Tube A has both ends open while tube B has one end closed, otherwise they are identical. The ratio fundamental frequency of tube A and B is (a) 1 : 2 (b) 1: 4 (c) 2 : 1 (d) 4 : 1 Q35 When temperature increases, the frequency of a tuning fork (a) increases (b) decreases (c) remains same (d) increases or decreases depending upon the material Q36 Two waves of wavelengths 99 cm and 100 cm both traveling with velocity 396 m/s are made to number of beats produced by them per second are (a) 1 (b) 2 (c) 4 (d) 8 Q37 of y = 2 (cm) sin interfere. The , what is the maximum acceleration of the particle doing the SHM (a) (b) (c) (d) Q38 A cylindrical tube open at both the ends, has a fundamental frequency ‘f’ in air. The tube is dipped vertically in air. The tube is dipped vertically in water so that half of it is in water. The fundamental frequency of the air column in now (a) f/2 (b) 3 f/4 (c) f (d) 2f Q39 A wave is represented by the equation y = a cos (kx − wt) is superimposed with another wave to wave such that point x = 0 is a node. The equation for the other wave is (a) a sin (kx + wt) (b) − a cos (kx − wt) (c) − a cos (kx + wt) (d) − a sin (kx − wt) Q40 An organ pipe open at one end is vibrating in first overtone and is in resonance with another pipe ends and vibrating in third harmonic. The ratio of length of two pipes is (a) 1 : 2 (b) 4 : 1 (c) 8 : 3 (d) 3 : 8 form a stationary open at both [ Chemistry ] Q41. In the reaction, H2(g) + I2(g) 2HI(g) the concentration of H2, I2 and HI at equilibrium are 28.0 moles are litres respectively. What will be the equilibrium constant (a) 30.61 8.0 , 3.0 and (b) 32.66 (c) 29.40 (d) 20.90 Q42. For a gas reaction, 3H2(g) + N2(g) 2NH3(g), the partial pressures of H2 and N2 are 0.4 and 0.8 atmosphere, respectively. The total pressure of the entire system is 2.8atmosphere. What will be the value of Kp if all the concentration are given in atmosphere ? (a) 32 atm-2 (b) 20 atm-2 (c) 50 atm-2 (d) 80 atm-2 Q43 One mole of nitrogen and three moles of hydrogen are mixed in a 4 litre container. If 0.25 percent of nitrogen is coverd to ammonia by the following reaction N2(g) + 3H2(g) 2NH3(g). What will be the equilibrium constant (Kc) in concentration units ? What will be the value of K for the following equilibrium - N2(g) + H2(g) (a) 1.49 x 10-5 lit mol-1 (b) 2.22 x 10-10 lit2 mol-2 (c) 3.86 x 10-3 lit mol-1 (d) Question is incomplete NH3(g). Q44 When ethanol and acetic acid were mixed together in equilimolecular proportion 66.6% are converted into ethyl acetate. Calculate Kc . Also calculate quantity of ester produced if one mole of acetic acid is treated with 0.5 mole and 4 mole of alcohol respectively. (a) 4, 0.93, 0.43 (b) 0.93, 4, 0.43 (c) 0.43, 0.93, 4 (d) 4, 0.43, 0.93 Q45 One mole of ammonium carbonate dissociate as shown below at 500 K. NH2COONH4(s) 2NH3(g) + CO2(g) If the pressure exerted by the released gases is 3.0 atm, the value of Kp is. (a) 7 atm (b) 3 atm (c) 4 atm (d) 8 atm Q46 Iron filling and water were placed in a 5 litre tank and sealed The tank was heated to 1273 K. Upon analysis the tank was found to contain 1.10 gram of hydrogen and 42.5 gm of water vapour. If the reaction in the tank is represented by 3Fe(s) + 4H2O(g) Fe3O4 (s) + 4H2(g) the equilibrium constant will be (a) 2.949 x 103 (b) 6.490 x 103 (c) 4.940 x 103 (d) 3.200 x 103 Q47 At 700 K, the equilibrium constant KP, for the reaction 2SO3(g) 2SO2(g) + O2(g) is 1.8 x 10-3 kPa. What is the numerical value of Kc for this reaction at the same temperature (a) 3.09 x 10-7mole litre-1 (b) 9.03 x I 0-7mole litre-1 (c) 5.05 x 10-9 mole litre-1 (d) 5.05 x 10-5mole litre-1 Q48 The value of KC for the reaction N2(g) + 3H2(g) 2NH3(g) is 0.50 at 400 °C. What will at 400 °C when concentration are expressed in mole litre-1 and pressure in atmosphere (a) 1.64 x 10-4 (b) 2.80 x 10-6 (c) 2.80 x 10-4 (d) 1.64 x 10-6 Q49 The equilibrium constant for the reaction H2(g) + S(s) respectively. The enthalpy of the reaction will be - H2S(g) ; is 18.5 at 935 K and 9.25 be the value of KP at 1000 K (a) - 68000.05 J mol-1 (b) -71080.57 J mol-1 (c) -80071.75 J mol-1 (d) 57080.75 J mol-1 Q50 Inhibitor is (a) An activator (b) Negative catalyst (c) Catalyst for a catalyst (d) Promoter Q51 KP for the reaction A(g) + 2B(g) 3C(g) + D(g) ; is 0.05 atm. What will be its KC at 1000 K in terms of R - (a) (b) (c) R (d) none of these Q52 The vapour density of N2O4 at a certain temperature is 30. The percentage dissociation of N2O4 at temperature is (a) 55.5 % (b) 60 % (c) 70 % (d) 53.3 % Q53 If PCl5 is 80 % dissociation at 523 K. Calculate the vapour density of the equilibrium mixture at 523 (a) 75.9 (b) 57.9 (c) 97.5 (d) 95.7 Q54 Ammonium carbamate when heated to 200 °C gives a mixture of vapours (NH2COONH4 2NH3 + CO2) with a density 13.0. What is the degree of dissociation of ammonium carbamate (a) 1 (b) 2 (c) 3 (d) 4 Q55 The volume of a closed reaction vessel in which the equilibrium 2SO2(g) + O2(g) 2SO3(g) sets is halved, Now(a) The rates of forward and backwards reactions will remain the same. (b) The equilibrium will not shift. (c) The equilibrium will shift to the right. (d) The rate of forward reaction will become double that of reverse reaction and the this K equilibrium will shift to the right. Q56 H2(g) + I2(g) 2HI(g) When 46g of I2 and 1g of H2 are heated at equilibrium at 450 °C, the equilibrium mixture contained How many moles of I2 and HI are present at equilibrium (a) 0.0075 & 0.147 moles (b) 0.0050 & 0.147 moles (c) 0.0075 & 0.347 moles (d) 0.0052 & 0.347 moles Q57 A two litre flask contains 1.4 gm nitrogen and 1.0 gm hydrogen. The ratio of active mass of nitrogen would be (a) 1 : 3 (b) 1 : 5 (c) 1.4: 1 (d) 1 : 10 1.9 g of I2. and hydrogen Q58 In the reaction A+B C+D The initial concentration of A is double the initial concentration of B. At equilibrium the concentration found to be one third of the concentration of C. The value of equilibrium constant is (a) 1.8 (b) 1.008 (c) 0.0028 (d) 0.08 Q59 of B was The value of KC for the reaction : A + 3B 2C at 400 °C . Calculate the value of KP (a) 1.64 x 10-4 (b) 1.6 x 10-6 (c) 1.6 x 10-5 (d) 1.6 x 10-3 Q60 Two moles of ammonia was introduced in an evacuated vessel of 1litre capacity. At high temperature undergoes partial dissociation according to the equation 2NH3(g) N2(g) + 3H2(g) At equilibrium the concentration of ammonia was found to be 1 mole. What is the value of ‘K’ ? the gas (a) 3/4 = 0.75 mol2 (b) 3/2 = 1.5 mol2 (c) 27/16 = 1.7 mol2 (d) 27/64 = 0.42 mol2 Q61. Q62 Which sodium salt will be heated with soda lime to obtain propane – (a) CH3 – CH2 – C – OΘNaÅ (b) CH3 – CH2 – CH2 – C – OΘNaÅ || || O O (c) CH3 – CH – C – OΘNaÅ (d) 2nd and 3rd both || O Which of the following compounds cannot be prepared by Wurtz reaction (a) CH3CH3 (b) CH3CH – CH | CH3 (c) (CH3)2CHCH3 (d) CH3CH2CH2CH3 (a) a, b (b) b, c (c) c, d (d) none of these Q63 Which of the following compounds liberate methane when treated with excess of methyl magnesium dry ether (a) CH3 - CH2 - CH2OH (b) H3C - CH2 - C ≡ CH (c) H3C - CH2 - CO2H (d) H3C - CH2 - CHO (a) a, b (b) b, c (c) a, b, c (d) All above Q64 Raney Nickel is a suitable catalyst for: (a) Bromination (b) Dehydration (c) Hydrogenation iodide in (d) Alkylation Q65. Correct order of boiling point is (a) n-Pentane < neohexane < isohexane < 3-methyl pentane (b) neohexane < n-pentane < isohexane < 3-methyl pentane (c) 3-methyl pentane < neohexane < n-pentane < isohexane (d) n-pentane < isohexane < 3-methyl pentane < neohexane Q66 In the complete combustion of Cn H2n + 2 , the number of oxygen rmoles required is (a) n / 2O2 (b) O2 (c) Q67 O2 (d) O2 What is X in the following sequence of reaction: X Z (a) Methane (b) Ethanoic acid (c) Propane (d) None of the above CH4 Q68. The number of isomers of C6H14 are: (a) 4 (b) 5 (c) 6 (d) 7 Q69. Which of the following reaction pairs constitutes the chain propagation step in chlorination of methyl (a) (c) ·CH3 + Cl2 ® CH3Cl + ·Cl CH3Cl + ·Cl ® CH2Cl2 + ·H CH3Cl + ·CI ® ·CH2Cl + HCl ·CH2Cl + ·CH2Cl ® CH2Cl + CH2Cl (b) (d) chloride? CH3Cl + ·Cl ® CH2Cl + HCl ·CH2Cl + Cl2 ® CH2Cl2 + ·Cl ·CH2Cl + Cl2 ® CH2Cl2 + ·Cl ·CH2Cl + ·Cl ® CH2Cl2 Q70 Kolbe's reaction is convenient for the preparation of: (a) Methane (b) Alkanes containing even number of carbon atoms (c) Alkanes containing even as well as odd number of carbon atoms (d) Alkanes containing odd number of carbon atoms Q71. For the formation of 27 gm of water, what volume of neopentane is required for the complete (a) 5.6 lit. (b) 11.2 lit. (c) 33.6 lit (d) 2.24 lit. Q72. Acetylene and ethylene reacts with alk. KMnO4 to give (a) Oxalic acid and formic acid (b) Acetic acid and ethylene glycol (c) Ethyl alcohol and ethylene glycol (d) None Q73. Chloroform when heated with silver powder gives an alkyne. For the substitution of hydrogen atom reaction must be carried out with (a) Cl2 at 0°C in the presence of ultra violet light (b) NaOCl at 0°C in the presence of light and air (c) Cl2 at 0°C in dark combustion: by chlorine the (d) None of the above Q74. Acetylene on passing into excess of HOCl solution forms (a) Ethylene chlorohydrin (b) Acetaldehyde (c) Dichloroacetaldehyde (d) Methyl Chloride Q75. 10 ml of a certain hydrocarbon require 25 ml of oxygen for complete combustion and the volume of produced is 20 ml. What is the formula of hydrocarbon (a) C2H2 (b) C2H4 (c) CH4 (d) C2H6 Q76. Lindlar's catalyst consists of (a) Metallic nickel + nickel boride, (b) Metallic platinum (c) Metallic palladium deposited on calcium carbonate containing lead acetate and quinoline (d) Sodium borohydride in ethanol. Q77. 2-Butyne and 1-Butene show resemblance in all except (a) Both decolourise alkaline KMnO4 (b) Both turn bromine water colourless (c) Both undergo addition reaction (d) Both from white precipitate with Tollen's reagent Q78. Acetylene reacts with formaldehyde in the presence of sodium alkoxide to form mainly (a) CH2 = CH – CH2OH (b) CH2OH – CH = CH2 CO2 (c) (d) Q79. Acetylene reacts with 42% H2SO4 containing 1% HgSO4 to give: (a) C2H5HSO4 (b) CH3CHO (c) HCHO (d) CH2 == CH2 Q80. The alkene which on ozonolysis yields acetone is: (a) CH2 == CH2 (b) CH3 –– CH == CH2 (c) (CH3)2C == C(CH3)2 (d) CH3 –– CH == CH – CH3 [ Mathematics ] Q81 A car is parked by a driver amongst 25 cars in a row, not at either end. When he returns he finds are empty. The probability that both the neighboring places of driver’s car are vacant is (a) (b) (c) (d) that 10 places Q82 A is one of the six race horses which is to be ridden by one of the two jockeys B or C. It is 2 :1 that B rides A in which case all the horses are equally likely to win but if C rides, then A’s chances of wining are trebled. The odds against his winning are (a) 13 : 5 (b) 5 : 13 (c) 8 : 5 (d) 5 : 8 Q83 A and B play by throwing a pair of dice alternately. A wins if he throws 6 before B throws 7. If A their chances of wining the game are in the ratio (a) 28 : 33 (b) 29 : 32 (c) 30 : 31 (d) none Q84 Five coins whose faces are marked 2, 3, …. Are thrown. The probability of obtaining a total of 12 starts the game is (a) (b) (c) (d) Q85 The probability that a teacher will give an unannounced test during any class meeting is twice, the probability that he will miss at least one test is . If a student is absent Q86 Two cards are randomly selected from a deck of 52 playing cards. The probability that both the than 3 and less than 8 is cards are greater (a) (b) (c) (d) (a) (b) (c) (d) Q87 is Probabilities of teams A, B and C wining are (a) (b) respectively. Probability that one of these teams will win (c) (d) none Q88 If two squares are chosen at random on a chess board, the probability that they have a side in common is (a) (b) (c) (d) none Q89 A single letter is selected at random from the word PROBABILITY . The probability that it is a vowel is (a) (b) (c) (d) none Q90 if P(A Ç B) = , P( Ç )= , P(A) = p, P(B) = 2p, then the value of p is given by (a) (b) (c) (d) Q91 The probability that a leap year selected at random contains either 53 Sundays or 53 Mondays is (a) (b) (c) (d) Q92 A bag contains 50 tickets numbered 1, 2, 3 , ……., 50 of which five are drawn at random and ascending order of magnitude ( (a) (b) ). The probability that x3 = 30 is arranged in (c) (d) none Q93 A box contains 10 mangoes out of which 4 are rotten. 2 mangoes are taken out together. If one of to be good, the probability that the other is also good is them is found (a) (b) (c) (d) Q94 Three letters, to each of which corresponds an envelope, are placed in the envelopes at random. The that all the letters are not placed in the right envelope is (a) 1/6 (b) 5/6 (c) 1/3 (d) 2/3 Q95 Two athletes A and B participate in a race along with other athletes. If the chance of A wining the that of B wining the same race is 1/8, then the chance that neither wins the race is (a) 1/4 (b) 7/24 (c) 17/24 (d) 35/38 Q96 race is 1/6 and Six coins are tossed simultaneously. The probability of getting at least 4 heads is (a) 11/64 (b) 11/32 (c) 15/44 (d) 21/32 Q97 Dialing a telephone number an old man forgets the last two digits remembering that these are different random. The probability that the number is dialed correctly is (a) 1/45 (b) 1/90 (c) 1/100 (d) none Q98 If A and B are two independent events, the probability that both A and B occur is 1/8 and the neither of them occur is 3/8. The probability of the occurrence of A is (a) 1/2 (b) 1/3 (c) 1/4 (d) 1/5 Q99 is probability If three vertices of a regular hexagon are chosen at random, then the chance that they form an dialed at probability that equilateral triangle (a) 1/3 (b) 1/5 (c) 1/10 (d) 1/2 Q100 is 10 apples are distributed at random among 6 persons. The probability that at least one of them will (a) receive none (b) (c) (d) none Q101. If (tan–1 x)2 + (cot–1 x)2 = (a) – 1 (b) 1 (c) 0 (d) none of these Q102. cos–1 [cos (2 cot–1 ( , then x equals ))] is equal to (a) (b) (c) p/4 (d) 3p/4 Q103. The equation (a) no solution (b) unique solution (c) infinite number of solution (d) None of these has Q104. Two angles of a triangle are cot–1 2 and cot–1 3. Then the third angle (a) p/4 (b) 3p/4 (c) p/6 (d) p/3 Q105. Complete set of values of x satisfying [tan–1 x] + [cot–1 x] = 2, where [.] denotes the greatest (a) (cot 3, cot 2] (b) (cot 3, – tan 1] (c) (cot 3, 0) (d) None of these Q106. Complete solution set of the equation [cot–1 x] + 2[tan–1 x] = 0, where [.] denotes the greatest equal to (a) (0, cot 1) (b) (0, tan 1) (c) (tan 1, ¥) (d) (cot 1, tan 1) Q107. The trigonometric equation sin–1 x = 2 sin–1 a, has a solution (a) (b) all real values of a (c) (d) Q108. , then sin x is equal for: integer function, is integer function, is (a) (b) (c) tan a (d) Q109. is equal to: (a) (b) (c) (d) Q110. The value of is: (a) (b) (c) (d) none of these Q111. The number of real solutions of (a) 0 (b) 1 (c) 2 (d) infinite is: Q112. If (a) 1/2 (b) 1 (c) – 1/2 (d) – 1 Q113. The value of x for which sin (cot–1 (1 + x)) = cos (tan–1 x) is (a) 1/2 (b) 1 (c) 0 (d) – 1/2 Q114. The principal value of for 0 < |x| < is , then x equals: (a) – (b) (c) (d) (e) none of these Q115. The period of the function f(x) = sin4 x + cos4 x is (a) p (b) (c) 2p (d) none of these Q116. The value of (a) 1 is (b) (c) (d) 2 Q117. If then sin q is (a) but not (b) or (c) but not (d) none of these Q118. If sin (a + b) = 1, sin (a – b) = (a) 1 (b) – 1 (c) zero (d) none of these Q119. Number of solutions of the equation tan x + sec x = 2 cos x lying in the interval [0, 2p] is& (a) 0 (b) 1 (c) 2 (d) 3 Q120. In a triangle PQR, ÐR = p/2. If tan (P/2) and tan (Q/2) are the roots of the equation ax2 + bx + c = (a) a + b = c (b) b + c = a (c) a + c = b (d) b = c , then tan (a + 2b) tan (2a + b) is equal to: 0 (a ¹ 0) then Answ ers Organic Chemistry Fact Sheet Organic Chemistry Quick Fact Sheet Acidic power Order Why ? 1. III < II < I Farther the (–I) group (Cl), lesser the acidic strength 2. I < II < III Farther the (+I) group, greater the acidic power 3. II < I < III —CH3 is electron donating and — NO2 is electron attracting 4. II < I < III —CH3 is electron repelling; decreases acidic strength of phenol III < I < II — OCH3 group contains +M effect and decreases acidic poer. I < II < III — NO2 is electron attracting; III is more resonance stabilised than I and also than II. In I, only inductive effect is operative. I > II > III sp2 hybridised carbon of I, II are more el-ectronegative hence acid strength is inc-reased. Benzylic (C6H5CH2) is more stab-ilised than allylic (CH2==CHCH2). 8. I > II > III > IV Effect of one —COOH on the other decr-eases as its distance between them increases, (COOH)2 is maximum acidic. 9. II < III < I —NO2 is electron attracting (–I effect) 10. III < II < I —OH shows electron withdrawing nature at o - and m - and electron repelling at p -, o - isomer due to intramolecular bonding in salicylate ion is stronger than m - isomer 11. III < II < I —do— 12. I < III < II —NH2 is electron donating. 5. 6. 7. Section B Basic power 1. Order I > III > II Why ? lone pair on N is not used in resonance of -electrons in I. In II lone pair of the ring is itself used in delocalisation while that of outside ring in III. I > II > III > IV —OCH3 is strong electron donating group. This is due to ortho effect, all the aniline are less basic than psubstituted aniline due to steric hindrance. 3. I > II > III > IV I (hyper conugation and induction) II (induction) IV (ortho effect), ortho effect normally decreases basic nature. 4. II > I > III In II there is sp3 hybridised C, In I, sp2. NO2 is electron withdrawing. III > I > II lone pair on N is used in delocalisation of -electrons in aromatic amines while cyclohexyl is electron repelling (III); in II, lone pair on N is used by two benzene ring. 6. I > II > III > IV NO2 is electron-withdrawing, thus nitro-anilines are less basic than aniline. IV is less basic than III because —NO2 is closer and exerts a stronger inductive effect. 7. III > I > II phenyl and —COCH3 are electronwithdra-wing and —C6H5 < COCH3 8. I < II < III Electron donating nature of C2H5 > CH3 So more basic strength. 2. 5. 9. I < II < III ortho effect in I. 10. I < II < III ortho effect in (I) General series Order Why ? There is intermolecular H-bonding I. III has weak force of attraction and is most volatile. 1. I > II > III 2. B.P. of o, m, p-nitro phenol o<m<p Intramolecular H-bonding in oisomer makes it more volatile. I > II > IV > III —CHO group is easily oxidised compared to keto group due to redusing hydrogen. I > II > IV > III —do— I < II < III < IV Aldehydes are more hydrated than ketones. Halide makes C of carbonyl group more electropositive. I > II > III CH3 group decreases +ve charge on C hence nucleophilic attack. Reactivity of ... with Tollen’s reagent 3. 4. Reactivity of ... with Fehling’s solution Extent of hydration of 5. Electrophilic nature of ........ for nucleophilic attack 6. 7. Reactivity of isomeric 1°, 2°, 3° butyl halide towards elimination (E1 or E2) 3° < 2° < 1° Dehydration of 8. due to stability of intermediate carbocation IV < I < II < III Alcohol leading to increase in conjugation due to dehydration is more easily dehydration is more easily dehydrated. IV is vinylic, hence least. I < II < III < IV < V < VI Substituted alkenes are more stable.More the alkyl groups are attached to the doubly bonded carbon atom more is the stability. 9. Stability of Stability of 10. I < III < II II is more substituted than III (More hyperconjugation more stability) III > II > I > IV IV is vinylic while in conjugative, II allylic. I < IV < II < III III is 3° allylic and II is 1° allylic 3° < 2° < 1° More the stability of intermediate, greater the reactivity of chemical reaction. Stability of 11. Stability of 12. Dehydration of 13. 1°, 2°, 3° isomeric butyl alcohol 14. Boiling points of II > I > III I, II have H-bonding but electronegativity of O > N hence Hbonding in II > I Formation of 15. I > II > III > IV (easiest I) greater the stability, easier the formation of perticular species. I < II < III < IV < V < VI Vinyl < methyl 1° < 2° < 3° < allylic I < II < III ~ IV < V < VI < VII < VIII If acid is strong, its conjugate base is weak and greater the leaving tendency. I > II > III > IV >V As the size of the substituents on the —C increases, the tetrahedrally bonded interme. diate becomes more crowded and these slower the rate. 16. Reactivity of C—H bond (abstraction of H) Leaving nature (tendency) of ... in SN reaction. 17. Rate of esterification of the following acids with MeOH 18. 19. Relative reactivity of ... with electrophile in SE reaction I > II > IV > III > V —CH3 is o-, p-directing and responsible for activation. Relative reactivity of these compunds with electrophile inSE reaction 20. II > I > III > IV —CH3 is o-, p-directing due to activation while —COOH is mdirecting and deactivating group. 21. Relative reactivity of ... with electrophile in II > I > IV > II As the number of sp3 hybridised C atoms separating the ring from the positively charged substituent increases, deactivating effect decreases due to less electronegativity. SE reaction. is best able to donate electrons there by giving a very stable Activating effects of the following o, pdirectors. 22. II > I > III Relative reactivity of ... towards SN1 reaction 23. II > I > III Relative reactivity of ... towards SN1 and SN2 reaction 24. 25. Relative reactivity of ... with E+ (electrophile) in SE reaction. 26. Order of SN2 reactivity of alkoxide nucleophiles SN1 : III > II > I SN2 : II < II < I uncharged intermediate. In cross conjugation diminished its ability to donate electrons to an arenium ion. Intermediates are benzylic cations. So CH3O(electron repelling) gives greater stability through delocalisation while NO2 (electron attracting) decreases stability. SN1 : 1° < 2° < 3° alkyl halide SN2 : 3° < 2° < 1° alkyl halide II > I > III —NO2 deactivates benzene ring for SE I < IV < V < III < II SN2 reactivity is suseptible to steric hindrance by the nucleophile as well as by the size of alkyl group. IMPORTANT ORDER AND FACTS OF ORGANIC CHEMISTRY 1. RCOCl > RCOOCOR > RCOOR > RCONH2 Nucleophilic substitution reaction. 2. HI > HBr > HCl > RCOOH > C6H5OH > H2O > CH CH > NH3 (Acidic nature). 3. CCl3CHO > HCHO > CH3CHO > CH3COCH3 Nucleophilic addition reaction. 4. CH2 = CH2 > CH CH > C6H6 Electrophilic addition reaction. Electrophilic Substitution Reaction Nucleophilic Substitution Reaction Nucleophilic Substitution Reaction 10. (CH3)2C = C(CH3)2 > CH3 - CH = C -(CH3)2 > CH3 - CH = CH - CH3 > CH3 - CH = CH2 (Stability) (Heat of Hydration) 13. NI3 > NBr3 > NCl3 > NF3 (Basic strength) 14. Br2 > Cl2 > I2 (Selectivity for halogenation) 15. Halogenation of alkenes by cyclic halonium state, so anti attack takes place. 16. Hydroboration followed by oxidation is always anti markownikoff’s addition due to steric effect. 17. Oximercuration - demercuration is m.K. addition of water because some carbocation character in cyclic mercurium state. 18. CHCl3 in the presence of strong bases forms biradical : CCl2 which undergo addition with double or triple bonds. 19. When conjugated diene reacts with alkene or alkyne it is known as diel’s elder synthesis. 20. Ozonolysis of cyclo alkene forms one mole dialdehyde while ozonolysis of cyclo alkadiene forms two moles of dialdehyde. 21. Ozonolysis with (CH3)2S is known as reductive ozonolysis. 22. Hydration of alkyne occur’s in HgSO4 and dil H2SO4. 24. Cis-2-butene reacts with Br2 to forms dl( ) pair of enantiomers of 2,3-dibromobutane while in case of trans-2-butene forms meso-2,3-dibromo butane due to anti addition always. 25. Haloform test given by species with CH3CO-group but not in case of A.A.E. and tert. Butyl alcohol. 26. Chloral reacts with chloro benzene in con. H2SO4 to form insectiside DDT. 27. NBS is used for free radical allylation. 28. Rate for SN1 reaction is 3° > 2° > 1° in protic polar solvent. 29. Rate for SN2 reaction is 1° > 2° > 3° in polar aprotic solvent like DMSO, DMF, HMPT. 30. Chemical reactions like Hoffmann carbylamine and Reimer Tiemann’s reaction active species is biradical CCl2. 31. If cyclo 1,3-penta diene reacts with CHCl3 and potassium tert. butoxide to form chlorobenzene. 32. Alkyl halides reacts with AgCN to form isocyanides due to ambident nature of nucleophile, other ambident nucleophiles are and SO3-2. 33. In dehydration of alcohols active species is carbocation so rearrangement occurs like hydride shift or alkyl shift. 34. Dehydration of cyclobutyl methyl alcohol ring expansion takes place, formation of cyclo pentene occurs. 35. In esterification where acid reacts with alcohol to form ester, - OH given by acid while - H by alcohol 36.Ether’s reacts with HI to form alcohol and halide where fission of lower ether by SN2 mechanism while higher ethers like ter. butyl methyl ether or alkyl methyl ether by SN1 mechanism. 37. Quantitative estimation of ethers is done by ziesal’s method. 38. If unsym. cyclic ether undergo fission it depends upon medium weather it is acid or basic like in acidic medium some character of carbocation so nucleophile goes to carbon where more alkyl groups are there while reverse in basic medium due to steric factor. 39. Aldehydes are reducing agent while ketones are not. 40. Aldehydes and ketones are separated by tollen’s reagent. 41. Carbonyl and noncarbonyl are seprated by sodium bi sulphite and bradye’s reagent. 42. As the size of alkyl group increases steric hindrance comes into play, reactivity towards nucleophilic addition decreases. 43. Aldehydes with hydrogen atom in the presence of dil base undergo enolization and form to give aldol product. 44. If there is two-CHO group with carbonian hydrogen atom to form cyclic intra aldol product. 45. Aldehydes without -hydrogen atom in the presence of con. alkali to form each molecule of acid and alcohol by hydride active species. 46. Glyoxal reacts with con. KOH to form glycolate ion by Intra Cannizaro’s. 47. Pinacol pinacolone type reactions involve protonation, deprotonation and alkyl shift. 48. Aldol, Perkin, reformatsky and knovengel’s reactions are classified as carbanian active reaction. 49. In Beckmann’s rearrangement migration of group which is anti to-OH group takes place. 50. Beckmann’s rearrangent is a reaction of oximes in the presence of H2SO4 or PCl5 to produce N-alkyl amide derivatives. 51. Migratory attitude of alkyl group in Pinacol-pinacolone, beckmann’s and bayer villegar oxidation is - C6H5 > (CH3)3C - > (CH3)2CH - > C2H5 - > CH352. Cyclo hexanoneoxime on beckmann’s reaction gives caprolectum which on reaction with polymer nylon-6 53. 2-methyl propanal even contains to give -hydrogen atom but does not give aldol reaction. 54. Diphenyl glyoxal reacts with con. KOH to form salt of benzillic acid. 55. Propanone in the presence of dry HCl gas by enolic intermediate to form diacetone alcohol undergo heating form mesityl oxide. If this again reacts with propanone to form phoron. 56. Benzaldehyde reacts with alc. KCN to form Benzoin which on oxidation form benzil. 57. By wittig reaction carbonyl compounds are converted into E-Z form of alkene. 58. Benzaldehyde do not respond to benedict’s and fehling’s solution due to less redusing power of aromatic aldehyde. 59. HCOOH respond to oxidising agent due to presence of - CHO group. 60. HI > H2SO4 > HNO3 > RCOOH > H2CO3 > C6H5OH > H2O > CH CH > NH3 > CH3 - C CH > CH2 = CH2 > H2 this is decreasing acidic nature. 61. Acids with -hydrogen atom when reacts with halogen in the presence of P to form -haloacid (HVZ). 62. Carboxyllic acid on reaction with PCl5, CH2N2 and H2O to form higher acid or next homologue. 63. For reactivity of acid derivatives use funda weaker the base better the leaving group. 64. Acid amide on reaction with PCl5 to form alkane nitrile. 65. Anhydride on reaction with carbonyl compound in the presence of base (carbanian) forms unsaturated carboxyllic acid (perkin reaction) , - 66. Amide on reaction with Br2 and alkali to form primary amine of lower homologue. Intermediate species is nitrene which undergo intra rearrangement to form RNH2. 67. Ester’s with -hydrogen atom in the presence of strong base to form carbanian undergo nucleophilic substitution reaction forms -keto ester for example ethyl acetate in the presence of pot. ter. Butoxide form aceto acetic ester (AAE). reaction is known as clesen’s ester condensation of four types (a) Simple clesen’s ester condensation. (b) CROSS clesen’s ester condensation. (c) Intra CEC (Dieckmann’s condensation). (d) mixed clesen ester condensation. 68. For a compound to be aromatic it must be cyclic, planar and obey (4n + 2) electron rule. 69. Cyclooctatetraene is non aromatic compound while pyrrole, pyredene, furan, cyclopentadieneylanion all are aromatic. 70. In aromatic electrophilic substitution reaction there is no hydrogen isotopic effect except sulphonation and iodination. 71. m- directing groups like nitrobenzene and benzaldehyde cannot undergo fridal craft reaction. 72. Phenol is less acidic than general carboxylic acid, cannot react with NaHCO3. 73. Anilene is more reactive than phenol towards electrophilic substitution reaction because less energy difference between nitrogen and carbon. 74. Benzene diazonium chloride reacts with phenol or anilene to form azo compounds. 75. C6H5NH2 > C6H5OH > C6H5OR > C6H5Br > C6H5NO2 (Reactivity towards electrophilic substitution reaction. AIEEE Minor Test #1 Ques 1 -12 [1. 5 marks] / Ques 13- 25 [3 marks] / Ques 26- 40 x 4. 5 marks -ve marks are one third Test duration 2 hour Q1. The triangle with vertices (1, 5); (–3, 1) and (3, –5) is (a) isosceles (b) equilateral (c) right angled (d) None of these Q2. If the points (4, – 4), (– 4, 4) and (x, y) form an equilateral triangle then (a) (b) (c) (d) None of these Q3. If (–4, 6), (2, 3) and (2, –5) are vertices of a triangle, then its incentre is (a) (–1, 2) (b) (2, –1) (c) (1, 2) (d) (2, 1) Q4.Circumcentre of a triangle whose vertex are (0, 0), (4, 0) and (0, 6) is (a) (b) (0, 0) (c) (2, 3) (d) (4, 6) (d) (0, 0) (d) 37.5 Q5.Orthocentre of a triangle whose vertex are (8, –2), (2, –2) and (8, 6) is (a) (8, –2) (b) (8, 6) (c) Q6.The area of a triangle with vertices (3, 8); (–4, 2) and (5, –1) is (a) 40.5 (b) 36.5 (c) 3.75 Q7.If D, E, F are mid points of the sides AB, BC and CA of a triangle formed by the points A(5, -1) B(-7, 6) and C(1, 3), then area of DDEF is (a) 2/5 (b) 5/2 (c) 5 (d) 10 Q8. The point (4, 1) undergoes two successive transformations (i) Reflection about the line y = x (ii) Translation through a distance 2 units along the positive direction of x – axis The final position of the point is given by the coordinates (a) (4, 3) (b) (3, 4) (c) (7/2, 7/2) (d) Q9.If A(c, 0) and B(– c, 0) are two points, then the locus of a point P which moves such that PA2+ PB2 = AB2 is (a) x2 – y2 =c2 (b) y2 = 4cx (c) x2 + y2 = c2 (1, 4) (d) None of these Q10. Let A(2, 3) and B(–4, 5) are two fixed points. A point P moves in such a way that DPAB = 12 sq. units, then its locus is (a) x2 + 6xy + 9y2 + 22 x + 66y – 23 = 0 (b) x2 + 6xy + 9y2 + 22 x + 66y + 23 = 0 (c) x2 + 6xy + 9y2 – 22 x – 66y – 23 = 0 (d) None of these Q11.If sum of square of distances of a point from axes is 4, then its locus is (a) x+y=2 (b) x2 + y2 = 16 (c) x+y=4 (d) x2 + y2 = 4 Q12.The extremities of diagonal of a right-angled triangle are (2, 0) and (0, 2), then locus of its third vertex is (a) x2 + y2 – 2x – 2y = 0 (b) x2 + y2 + 2x – 2y = 0 (c) x2 + y2 – 2x + 2y = 0 (d) x2 + y2 + 2x + 2y = 0 Q13.Keeping coordinate axes parallel, the origin is shifted to a point (1, –2), then transformed equation of x2 + y2 = 2 is (a) (c) x2 + y2 + 2x – 4y + 3 = 0 x2 + y2 – 2x – 4y + 3 = 0 (b) x2 + y2 – 2x + 4y + 3 = 0 (d) x2 + y2 – 2x + 4y + 3 = 0 Q14.To remove xy term from the second degree equation 5x2 + 8xy + 5y2 + 3x + 2y + 5 = 0, the coordinates axes are rotated through an angle q, then q equals (a) p/2 (b) p/4 (c) 3p/8 (d) p/8 Q15.The ratio in which the line y – x + 2 = 0 divides the line joining (3, – 1) and (8, 9) is (a) 2:3 (b) 3:2 (c) –2:3 (d) –3:2 Q16.The area of the triangle, formed by the straight lines 7x – 2y + 10 = 0, 7x + 2y – 10 = 0 and 9x + y + 2 = 0, is (a) (b) (c) (d) None of these Q17.Two vertices of a triangle are (3, – 1) and (– 2, 3) and its orthocenter is origin, the coordinates of the third vertex are (a) (b) (c) (d) Q18.The equation of the internal bisector of ÐBAC of DABC with vertices A(5, 2), B(2, 3) and C(6, 5) is (a) 2x + y + 12 = 0 (b) x + 2y – 12 = 0 (c) 2x + y – 12 = 0 (d) Q19.The equation of the straight line upon which the length of perpendicular from origin is angle of 75° with the positive direction of x – axis, is (a) (b) (c) (d) None of these units and this perpendicular makes an None of these Q20.The image of the point (– 8, 12) with respect to the line mirror 4x + 7y + 13 = 0 is (a) (16, – 2) (b) (– 16, 2) (c) (16, 2) (– 16, – 2) (d) Q21.The equation of the straight line passing through the point of intersection of lines 3x – 4y – 7 = 0 and 12x – 5y – 13 = 0 and perpendicular to the line 2x – 3y + 5 = 0 is (a) 33x + 22y + 13 = 0 (b) 33x + 22y – 13 = 0 (c) 33x – 22y + 13 = 0 (d) None of these Q22.If the family of lines x(a + 2b) + y(a + 3b) = a + b passes through the point for all values of a and b, then the coordinates of the points are (a) (2, 1) (b) (2, – 1) (c) (– 2, 1) (d) None of these Q23.The value of k so that the lines 2x – 3y + k = 0, 3x – 4y – 13 = 0 and 8x – 11y – 33 = 0 are concurrent, is (a) 7 (b) –7 (c) 5 (d) –5 Q24.Let P be the image of the point (– 3, 2) with respect to x-axis. Keeping the origin as same, the coordinate axes are rotated through an angle 60° in the clockwise sense. The coordinates of point P with respect to the new axes are (a) (b) (c) (d) Q25.If for a variable line drawn from origin to this is None of these , the condition a–2 + b–2 = c–2 (c is a constant) is satisfied, then the locus of foot of the perpendicular (d) x2 – y2 = c2 (d) none of these (d) none of these Q29.Let R be reflexive relation on a finite set A having n elements, and let there be m ordered pairs in R. Then (a) m³n (b) m£n (c) m=n (d) none of these (a) (b) x2 + y2 x2 + y2 = 2c2 (c) x2 + y2 = c2 = Q26.If A and B are two sets, then A (A È B)¢ equals (a) A (b) B (c) f Q27.Which of the following is an empty set ? (a)The set of prime numbers which are even (b)The solution set of the equation (c)(A x B) Ç (B x A), where A and B are disjoint (d)The set of real which satisfy x2 + ix + i – 1 = 0 =0;xÎR Q28.If sets A and B are defined as : A = {(x, y) : y = , x ¹ 0, x Î R} , B = {(x, y) : y =-x, x Î R}, then (a) AÇB=A (b) AÇB=B (c) AÇB=f Q30.f(x) = | sin x | has an inverse if its domain is : (a) [ 0, p ] (b) Q31.Consider the following equations (1) A – B = A – (A Ç B) (2) A = (A Ç B) È (A – B) (2) A – (B È C) = (A – B) È (A - C) (c) (d) none of these Which of these is / are correct (a) 1 and 3 (b) 2 only (c) 2 and 3 (d) 1 and 2 Q32.If a is the set of the divisors of the number 15, B is the set of prime numbers smaller than 10 and C is the set of even numbers smaller than 9, then (A È C) Ç B is the set (a) {1, 3, 5} (b) {1, 2, 3} (c) {2, 3, 5} (d) {2, 5} Q33.x, y and z are rational numbers. Consider the following statements in this regard (1) x+3=y+zÞx=y (2) Which of the above statement(s) is / are correct ? (a) 1 alone (b) 2 alone (c) xz = yz Þ x = y Both 1 and 2 (d) Neither 1 nor 2 Q34.If second term of an AP is 2 and 7th term is 22, then sum of 9 terms is (a) 126 (b) – 126 (c) 90 (d) 252 Q35.If Sn denotes the sum of the first n terms of an AP and S2n = 3Sn, then (a) 7 (b) 6 (c) 8 (d) 10 , then the ratio of the 7th term and 5th term of the AP is Q36.The sum of r terms of an AP is denoted by Sr and (a) (b) (c) (d) Q37.A square is drawn by joining the mid points of the given square a third square in the same way and this process continues indefinitely. If a side of the first square is 16 cm, then the sum of the areas of all the squares (a) 128 sq cm (b) 256 sq cm (c) 512 sq cm (d) 1024 sq cm Q38.If the pth term of an AP is (a) 0 and qth term is then the sum of the first pq terms is (b) (c) (pq – 1) (d) (pq + 1) Q39.If the AM between pth and qth terms of an AP be equal to AM between rth and sth terms of the AP, then (a) p+s=q+r (b) p+q=r+s (c) p+r=q+s (d) p+q+r+s=0 Q40.The value of 5 + 55 + 555 + …… to n terms is (a) 10n + 1 – 10 (b) (c) (d) [10n + 1 – 1 + 9n] (10n + 1 – 10) Answ ers Question 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Answer c c a c a d b b c c d a a b a a b c a d a b b a c Question 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Answer c c c a b d a d a b d c c b b ATOMIC STRUCTURE Introduction The most special thing about this chapter is that the no. of scientists involved in developed of this concept is remarkably large. Starting with heucippus of Miletus in 440 BC it extends to 2000's. And the research is still going on. Even the great scientist EINSTEIN had his hands in developing this extraordinary concept. Atomic No.: Total no. of protons present in nucleus. Mass No.: Total no. of protons & Neutrons in neucleus. Atomic No.(Z): no. of electrons (when atom is neutral). Mass No.(A): no. of neutrons + no. of protons. Representation Ilustration: Calculate no. of protons, neutrons & electrons in . Ans: Z = 35, A = 80 No. of protons = Z = 35 No. of neutrons = A - Z = 80 - 35 = 45 As atom is neutral. No. of electrons = No. of protons = 35. Isotopes: Such atoms of same element having same atomic no. but different mass no.s are c/d isotopes. Protiun ( ). Denterium ( ) & Tritium ( ) are isotopes. Isobars: Atoms of different elementswhich have same mass no.s but different atomic No. , , are isobars. Isotones: Atomes of different elements which contain same no. of neutrons c/d isotones. , are isotones because they have same no. of neutrons. subatomic particle like electron at high speed varies. m= m0 restmass c velocity of light Photoelectric effect: When radiations with certain minimum frequency (v0) strike surface of metal electrons are ejected from surface of metal. This is c/d photoelectric effect & electrons are called photoelectrons. Threshold frequency: It is min. frequency (v0) below which no electrons are ejected. Work function: Min. energy required to eject electron (h 0). h = h 0 + mv2 Total energy = Workfunction + Kinetic energy. Planck's Quantam Theory: (i) Radiant energy is emitted or absorbed not continuously but discontinuously in form of small discrete packets of energy. Each packet c/d 'quanta'. In case of hight energy 'quanta' is 'photon'. (ii) Energy of each quantum is directly proportional to frequency of radiation. E=h h Planck's Constant. h = 6.626 x 10-34 J/sec. Body will be some whole no. quanta. E = nh n integer. Illustration: Calculate KE of electrons ejected when yellow light of frequency 5.2 x 1014 s-1 on a metal whose threshold frequency is 4 x 1014 s-1. Ans: h h =h -h 0 + mv2 = mv2 mv2 = h(1.2 x 1014) -34 = 6.625 x 10 x 1.2 x 1014 = 7.95 x 10-20 J 0 Bohr's Model: Postulate: (1) As long as electrons occupy definite energy level, it does not radiate out energy. Emission or absorption of energy occures only when electrons jumps from one level to other. E = En2 - En1 = h If n2 > n1 emission epectra. If n2 < n1 absorption spectra. n1 n2 Initial state. Final state. (2) Angular momentum of electron in closed is always quantized i.e. integer multiple of Angular momentum = n mvr = n . . Dumb Question: Why angular momentum is mvr ? Ans: Angular momentum = Moment of Inertia x angular velocity. = Note: In CGS unit, MKS unit, = mvr =1 = 9 x 109 Nm2c-2. BOHR MODEL & X-RAYS Physics: Modern Physics Neils Bohr gave forward his model of atom with answeres most of the flaws that Rutherford model had. This model introduced quantization principal and this model is regarded as first quantum mechanical model. We will explore in detail, this structure of atom. We will also look into X - ray formation which is a converse process of photoclectric effect and will examine Moreley's law in pantium. THE BOHR THEORY OF HYDROGE ATOM (AND HYDROGEN LIKE ATOM) Bohr gave following postulates for electron in hydrogen atom :• An electron in an atom could resolve in certain stable orbits without the emission of radiant energy. • An electron resolves around the nucleus only in those orbits for which the angular momentum is some integral multiple of angular of electron is QUANTAIZED. L= , where n . Thus principal quantum number. • An electron might a transition from one of its specified non-radiating orbits to another of lower energy. When it does so, a single photon is amitted having energy equal to the energy difference between the initial and final slater. The frequency of emitted photon is given by h = Ei - Ef Dumb Question:- Are these equations valid for all atoms ? Ans:- No, equations are valid only for single electron system, i.e. systems where only one electron is present. Ideally this equation applies only to Hydrogen atom, Singly ionized helium He +, and doubly ionized Lithium Li+ +. In Bohr's model, radius of nth orbit is given by rn = and speed of electron is given by Vn = if values of constant are evaluate then, rn = 0.529 n2/z and Vn = 2.19 X 106 m/sec. where n Principal quantum number/shell number. z atomic number of nucleus involved. Why ?? from Bohr's postulate, angular momentum of electron in nth orbit is L = also from mechanics L = mvnrn mvnrn = ............................................... (1) for electron to resolve in its orbit, Electrostatic force is providing the required centripetal force. Solving (1) & (2) simultaneously yields the required result. BOHR MODEL & X-RAYS Physics: Modern Physics Bohr Energy levels:- The energy of a revolving electron is :(i) Kinetic Energy, due to its revolution in the orbit. (ii) Electrostatic Potential Energy. The total energy Eu is the sum of kinetic and potential energies. Eu = Ku + Vu = if the value of constants are placed then Eu = Dumb Question:- What is the significance of total energy of e- as a negative quantity? Ans:- Total energy as negative quantity sindicates that it is held in a stable state and energy needs to be supplied to it if electron has to be pulled out. Dumb Question:- Where has the zero of potential energy been let ? Ans:- The zero of electrostatic potential energy has been setup at infinity i.e. outside the bounds of atom. If an electron moves from ni orbit to lower nf orbit then it lose, energy which is emitted in the form of radiations and the wavelength of such radiation is given by formula. , Where R = Rydberg's constant = 1.097 x 107 m- 1 Why ?? energy of an orbit is given by En = from Bohr's postulate when an electron falls from higher orbit to lower orbit then energy of emitted radiation is given by E = Ei - Ef = if R = (constant) then Few named transitions :- Lymen Series n = 2, 3, 4,............... Balmen Series n = 3, 4, 5,............... Paschen Series n = 4, 5, 6,............... Brackett Series n = 5, 6, 7,............... Pfund Series n = 6, 7, 8,............... (In all these cases electron is moving down from nth orbit to concerned orbit) • Total number of emission lines from same excited state n 1 to another state n2 (< n1) is given by BOHR MODEL & X-RAYS Physics: Modern Physics few handy difinations:IONIZATION POTENTIAL:- The minimum energy needed to ionize an atom is called ionization energy, and the potential defference through which an electron should be accelerated to acquire this energy is called ionization potential. The ioniozation energy of hydrogen atom is ground state is 13.6 ev and ioniozation potentiation is 13.6 v. BINDING ENERGY:- Binding enrgy of a system is defined as energy liberated when its constituents are brought from infinity to form the system. For hydrogen atom binding energy is same as its ionization energy. EXCITATION ENERGY:- The energy required to take an atom from its ground state to an excited state is ncalled excitation energy of that excited state, and the potential. ILLUSTRATION:- Find the longest and shortest wavelength in the Lyman Series for Lydrogen. In what region of the electromagnetic spectrum does each series lie ? Solution:- The transition equation for Lyman Series is given by, , n = 2, 3, ........................ The longest wavelength is corresponding to n = 0 = 1.099 x 107(1 - 1/4) = 0.823 x 1s7 = 1.254 x 10- 7m = 1215 The shortest wavelength corresponds to n = = 1.097 x 107(1 min = 0.911 x 10-7 m = 911 ) AS can be seen both, the weavelength lie in ultraviolet (UV) region of electromagnetic spectrum. X-RAYS Electromagnetic radiations with wavelength from 0.1A 0 to 100A0 falls into the category of X - rays, however the boundaries of this catygory are not sharp. • The process of production of X-rays is reserve of photoelectric efffect. Here electromagnetic radiations are emitted by the bombordment of high speed thermionically emitted electrons on the metal surface. X-rays produced are of two types:(a) CONTIMUOUS X-RAYS:- When electrons of vary high kinetic energy accelarates in an electric field then according to Maxwells theory, it radiates energy in the form of electromagnetics waves X-rays produced in this fashion are called continuous X-rays (also called Bremsstrahlung). • Continuous X-rays produced at a given accelerating potential V very in wavelength, but none has wavelength shorten than a certain value ,V min. potential aeron which electron is accelerated. Dumb Question:- What is the significance of this minimum wavelength of the X-Ray ? Ans:- This minimum wavelength corresponds to the maximum energy of the X-ray produced. This condition occures when striking electron looses all its energy and this energy gets converted into X-rays. This for it Energy of X-ray = total kinetic energy of electron = energy gained when accelerated across potential barrier Note That the maximum wavelength 0 , this is the case when striking electron looses very small fraction of its energy. CHARACTERISTICS X-RAYS:- The sharp lines superimposed on the continuous spectrum are known as characteristic X-rays. because they are characteristic of the target material. s • Characteristic X-rays emission occures when a banbarding electron that collides with a target atom has sufficient energy to remove on inner shell electron from the atom. • The vacancy created in the shell is filled when an electron from a higher level drops down into it. This transition is of a photon whose energy equals the difference in energy between the two levels. Naming of characteristic X-rays:- Let the incoming electron dislodge an atomic electron from innermost shell - the K shell. If the vacancy is filled by an electron dropping from the next higher shell - the L shell emission is said to be of Kd series. If vacancy is filled by an electron dropping from M shell, Dumb Question:- Why do Ans:- represents transition from higher shell then the kd line, lower wavelength as line is produced and Jo an. occur earlier than Kd in the plot ? reperesents transition over larger energy range, thus would have . thats why occurs earlier than Kd. Electric Capacitance And Capacitor INTRODUCTION The capacitance of any conductor is its capacity to store charge. As the quantity of charge on conductor is increased its potential also increases. Beyond a limit even if a small additional charge is given then it starts leaking. Hence Q V or Q = CV. Where C is called capacitance of the conductor. It depends upon geometrical shape and size of the conductor. If V = 1 volt, then Q = C, hence capacitance of any conductor will be numerically equivalent to that charge which makes its potential equal to 1 volt. Unit of capacitance is ‘Farad’: 1 Farad = 1 coulomb/1 volt. = coulomb/ (joule/coulomb). = coulomb2/joule. = (ampere x second) 2 / ( Newton x meter). 3) Dimensions of capacitance: In practice 1 Farad is very large capacity therefore its small units are as following: 1) 1 micro-farad = 10-6 farad = 1f. 2) 1 nano-farad = 10-9 farad = 1f. 3) 1 pico-farad or micro-micro farad = 10-12 farad = 1f = 1f. 4) Capacitance of spherical conductor: For a spherical conductor of radius R, Potential is Fig (1) 1) . 2) C R. 3) C (capacitance) does not depend upon the charge given. 5) Energy stored in a charged conductor: 6) Redistribution of charge: Fig (2) Electric Capacitance And Capacitor INTRODUCTION Before contact: Q = Q1+Q2 = V1C1+V2C2 In contact or after contact Q11 = C1V Q21 = C2V And 7) Energy loss in redistribution of charge: 1) If V1 = V2, means two conductors have the same potential then energy loss is zero otherwise 2) V1>V2 or V2>V1; E will always be time positive. Hence, there will be loss of energy in the form of heat. 8) Capacitor (Parallel plate capacitor): It consist of two plates placed close together and is insulated from one another by air or same dielectric medium. One of the plates is given a charge and other is grounded. This device can store charge or electrical energy. 9) Different types of grouping of capacitors and the effective capacitance: 1) Series Combination: Fig (3) Remember V = V1 + V2 + V3 + -------------- 2) Parallel Combination: Fig (4) Remember: Q = Q1 + Q2 + Q3 + ----------------C = C1 + C2 + C3 + ----------------10) If n parallel plates are connected as shown in the figure below and C1 is the capacitance between two adjacent plates then total capacitance will be C C = (n-1) C1. Fig (5) Electric Capacitance And Capacitor INTRODUCTION 11) Capacitance of spherical capacitor: (A) When outer sphere is earthed. Fig (6) (B) When inner sphere is earthed: Fig (7) 12) Capacitance of cylindrical capacitor: Fig (8) Electric Capacitance And Capacitor INTRODUCTION 13) Capacitance per unit length between two parallel wires of radius r and separated by distance ‘d’: Fig (9) 14) The energy stored in a fully charged capacitor: E2 = Energy density. Where E is electric field in a capacitor. 15) Charging and discharging of capacitors: (a) Fig (10) (b) Fig (11) VC = E at t=0. (c) Fig (12) (d) Fig (13) HEAT TRANSFER Introduction Heat Transfer helps us to understand various aspects for the transfer of heat through various materials(solids, liquid and gasses) through various known process such as conduction, convection, radiation etc. So, it finds a great use in engineering applications. Heat is transferred from higher temperature to lower temperature. [secondary information] There are three different ways in which heat can be transferred: 1. Conduction:- it is process by which heat can be transferred in solids. 2. Convection:- it is aprocess by which heat is transferred in fluides (gaseous &liquid) 3. Radiation:- it is a process in which the heat is transferred in the form of electromagnetic waves without yhe aid of any material medium. Thermal conductivity: In solids, heat is transferred through conduction. We will study conduction of heat through a solid bar in the following sector. Consider a solid bar of thickness d and area of cross-section A. The left side of bar is maintained at QA temperature and right side at QB Let us suppose QAQB Heat flows from higher temperature to lower temperature after some time, the temp of each section becomes constant with time. This is known as steady state. In steady state, if Q Amount of heat crosses through any cross section in time T, then and or, K: coefficient of thermal conductivity. For a small thickness Dx along the direction of heat and whose thickness dx is small and temperature difference is Q [Secondary information] Quantity called the temperature gradient and minus sign indicates that is negative along the direction of heat flow. [Secondary Information] We can compose the equation with the Ohm's Law V1 - V2 = I.R I= Similarly hence is called thermal resistance rth. Rth = Accretion of Ice [Secondary Information]: Consider a layer of ice of thickness x has air temp - Q0c and is 00c. HEAT TRANSFER Introduction Considering unit cross -section area of ice , if alayer of thickness dx given in time dt, The heat given by thin layer. = mass x Latent heat = 1.dx. .L. = density of ice L = Latent heat of fusion of ice. The quantity of heat is conducted upward through the ice layer in time dt dx. .L. = Time taken Dumb Question: Q1: Pieces of iron and glass are heated to same temperature. which one will be more hot ? why ? A: Pieces of iron wil be hotter. Because of higher thermal conductivity. Q: Cooking utensils are provided wth wooden handes why ? A: Wood is pure conductor of heat. So hot utensils can be easily handled. Q: In winter, metallic handles of wooden door appear colder. Why ? A: Because they are good conductor of heat. Q: Why is ice packed in gunny bags or sawdust. A: Air trapped in saw dust prevent transfer of heat from the surroundings, to the ice. Illustration: Q: A cubical ice box of thermocole has each side = 30cm and a thickness of 5cm. 4kg of ice is put in the box. If outside temp is 450c and the coeff. of thermal conductivity = 0.01 J s-1 m-1 0c-1 Calculate the mass of ice left after 6 hrs. Take latent heat of fusion of ice = 335 x 103 J/kg. Solution: l = 0.3 m Thickness = 0.05 m Total surface area = 6l2 = 0.54 m2 T = 450c T = 6 hrs Q = mL = KA m = KA = 0.313 kg wt of ice left = 3.687 kg Radation: Absorptive Power a: Absorptive power of a body is defined as the fraction of the incident radiation that is absorbed by the body. Absorptive Power a = Emmisive Power E: The emmisive power denotes the energy radiated per unit time per unit area of the surface. Emmisitivity E: The emmisitivity of a surface is the ratio of the Emmisive power of the surface to the emmisive power of the black body at that temp. E= Black Body: A perfectly black body is the one which absorbs completely all the radiations of whatever wavelength incident on it. Kirchoff's Law: It states that the ratio of the Emmisive power to the Absorptive power for radiation of a given wavelength is the same for all bodies at the same temperature. [constant] [Secondary Information] Everything is continuously emitting radient energy in all direction at a rate depending only on the nature of the surface and its temperature and also it is absorbing radient energy from all surrounding bodies at arate depending on its surface and temperature of the surrounding bodies. HEAT TRANSFER Introduction Stefan's Law of Radiation: The total radient energy emitted E per unit time by a black body of surface A is propertional to the fourth power of its absolute temperature. E T4 4 or E = AT = Stefan's const For abody which is not black body E= AT4 = emmisitivity of te Black Body. Note: Emmisitivity and absorptive power have the same value. Net loss of thermal Energy[secondary information]: If abody of surface area A is kept at absolute temp T in asurrounding of temperature T0(T0 > T) Then the energy emitted by the body per unit time. E= AT4 And the energy absorbed per unit time by the body E0 = AT04 Net loss of thermal energy per unit time. E = E - E0 = A[T4 - T04] Newton's Law of Cooling: For a small temperature difference between a body and its surroundings, the rate of cooling of the body is dirctly propertional to the temperature difference. If abody of temperature T and surface area A is kept in a surrounding temperature T 0(T0 < T). Then net loss of thermal energy per unit time. = A(T0 - T00) If the temperature difference is small T = T0 + T)4] = => A[(T0 + => AT04[1 + 4 T A[T04 (1 + )4 - T04] + higher powers of - 1] 3 =4 AT0 T Now, Rate of loss of heat at temperature T mc =-4 AT03[T - T0] = - K[T - T0] K= (T - T0) WIENS LAW: At a const temperature T, when wavelength is increased , the energy emitted E, first increases, reaches a maximumand then decreases i.e at a particulartemperatuure the spectral radiancy is a maximum at a particular wavelength As the temperature increases , the maximum radiancy of energy occurs at shorter wavelength i.e b is a constant. This is called wiens Displacement Law. Dumb Question: mt = b m. Q: At a particular wavelength the bodies A, B, C, have their emmisive Power in Ratio 1:2:3. what is the ratio of the absorptive power ? A: 1:2:3 became = constant