Title States of Matter.pdf ✅

JEE JEE Advance (2024) Q1 If the distribution of molecular speeds of a gas is as per the figure shown below, then the ratio of the most probable, the average, and the root mean square speeds, respectively, is (A) 1:1:1 (B) 1: 1: 1.224 (C) 1: 1.128: 1.224 (D) 1: 1.128: 1 Q2 One mole of a monoatomic real gas satisfies the equation p(V – b) = RT where, b is a constant. The relationship of interatomic potential V(r) and interatomic distance r for gas are given by (A) (B) (C) (D) Q3 The approximate length of the side of a cube containing 850 million gas molecules at 0°C and 1 atm would be (N = 6 × 10 ) (A) 3.17 × l0 cm (B) 3.17 × l0 cm (C) 1 mm (D) 5.25 ×10 cm Q4 Quantities of 16 g of oxygen and 14 g of nitrogen are contained in a closed bottle. The pressure inside the bottle is 4 atm. Now, 8 g O gas is removed from the bottle. What will be the new pressure inside the bottle? (A) 2 atm (B) 4 atm (C) 6 atm (D) 3 atm Q5 For 10 minutes each, at 27°C, from two identical holes nitrogen and an unknown gas are leaked into a common vessel of 3 L capacity. The resulting pressure is 4.15 bar and the mixture Chemistry States of Matter - Gases and Liquids A 23 –4 –3 –4 2
JEE contains 0.4 mole of nitrogen. The molar mass of the unknown gas is (R = 0.083 L-bar/K-mol) (A) 112 g mol (B) 224 g mol (C) 242 g mol (D) 448 g mol Q6 Liquids P and Q form an ideal solution. The vapour pressures of pure liquids P and Q at 80°C are 300 mm and 100 mm of Hg, respectively. Suppose that the vapour above a solution composed of 1.0 mole of P and 1.0 mole of Q at 80°C is collected and condensed. This condensate is then heated to 80°C and vapour is again condensed to form a liquid R. What is the mole fraction of P in R? (A) 0.5 (B) 0.75 (C) 0.90 (D) 0.10 Q7 Which of the following can be separated into its pure components by fractional distillation? (A) C H + C H (B) H O + HCl (C) H O + HNO (D) H O + C H OH Q8 Pure water boils at 373 K and nitric acid at 359 K. The azeotropic mixture of water and nitric acid boils at 393.5 K. On distillation of the azeotropic mixture, (A) pure nitric acid will distil over first. (B) pure water will distil over first. (C) one of them will distil over with small amount of the other (D) both of them will distil over in the same composition as they are in the mixture. Q9 The value of Boyle’s law constant for an ideal gas at a certain temperature depends on (A) pressure of the gas. (B) volume of the gas. (C) amount of the gas. (D) temperature of the gas. Q10 At very high pressure, the compressibility factor of 1 mole of a van dcr Waals gas can be given as (A) (B) (C) (D) Q11 If the van der Walls equation is represented as in place of Z = the correct relation(s) is/are (A) B = B'RT (B) B = B'/RT (C) C = B + C'(RT) (D) C' = C/(RT) Q12 A mixture of liquids ‘A’ and ‘B' in the molar ratio 1 : 2 forms a maximum boiling azeotrope. Identify the incorrect statement, if ‘A’ is more volatile. (Molar masses: A = 100, B = 50). (A) A liquid solution of A’ and ‘B’ having mass % of A = 50 will have vapours having mass % of A = 50. (B) A liquid solution of A’ and ‘B’ having mass % of A > 50 will have vapours having mass % of A >50. (C) A mixture of A’ and ‘B’ in the molar ratio 1 : 3 can be separated into azeotropic mixture and pure A’. (D) A mixture of A’ and ‘B’ in the molar ratio 2 : 3 can be separated into azeotropic mixture and pure A’. Q13 Which of the following statement(s) is/are correct? (A) –1 –1 –1 –1 6 6 7 8 2 2 3 2 2 5 Z = 1 + bP RT Z = V V−b Z = V+b V Z = 1 − a VRT Z = = 1 + P + +. . . . , PVm RT B ′ C ′P 2 = 1 + + +. . . . , PVm RT B Vm C V 2m 2 2 2
JEE Minimum boiling azeotropic mixture boils at temperature lower than cither of the two pure components. (B) Maximum boiling azeotropic mixture boils at temperature higher than either of the two pure components. (C) Minimum boiling azeotropic mixture shows (+) ve deviation. (D) Maximum boiling azeotropic mixture shows (–) ve deviation. Q14 In which of the following liquid pair, there is contraction in volume on mixing? (A) C H + C H (B) H O + HCl (C) H O + HNO (D) H O + C H OH Q15 A liquid solution is formed by mixing 10 moles of aniline and 20 moles of phenol at a temperature where the vapour pressures of pure liquid aniline and phenol are 90 and 87 mm Hg, respectively. The possible vapour pressure of solution at that temperature is x, then the value of x is: Q16 Find the number of diffusion steps required to separate the isotopic mixture initially containing some mass of hydrogen gas and 1 mole of deuterium gas in a 3 litre container maintained at 24.63 atm and 300 K to the final mass ratio of hydrogen to deuterium gas equal to 1 : 4. Q17 An LPG (liquefied petroleum gas) cylinder weighs 14.8 kg when empty. When full, it weighs 28.8 kg and shows a pressure of 35 atm. In the course of use at 300 K, the weight of the full cylinder is reduced to 23.2 kg. Assume LPG to be n-butane with normal boiling point of 273 K. If the volume (in litre) of the gas used up at the normal usage conditions, and Y = final pressure (in atm) inside the cylinder then the value of is (R = 0.08 L-atm/K-mol) Q18 A quantity of 4 ml of a gas at 1 atm and 300 K is dissolved in 1 L of water. The volume (in ml) of gas that will dissolve in 0.5 L of water at 4 atm and 300 K is Q19 A ‘100 proof’ solution of ethanol in water consists of 50.00 ml of C H OH(l) and 50.00 ml of H O(l) mixed at 15.56°C. The density of the solution is 0.9344 g/ml, that of pure H O is 1.0000 g/ml and that of pure C H OH is 0.7939 g/ml. Is the solution ideal? Answer ‘1’, if the solution is ideal and answer ‘2’, if the solution is non–ideal. Q20 At 323 K, the vapour pressure (in mm Hg) of a methanol−ethanol solution is represented as P = 120X + 140, where X is the mole fraction of methanol in liquid solution at equilibrium. The value of P is Y then determine the value of Y. 6 14 6 6 2 2 3 2 2 5 X = ×1 100 (X+Y) 10 2 5 2 2 2 5
JEE Answer Key Q 1 ( B ) Q 2 ( C ) Q 3 ( A ) Q 4 ( D ) Q 5 ( D ) Q 6 ( C ) Q 7 ( A ) Q 8 ( D ) Q 9 ( C, D ) Q10 ( A, B ) Q11 ( A, C ) Q12 ( C ) Q13 ( A, B, C, D ) Q14 ( B, C ) Q15 (88.00) Q16 (04.00) Q17 (242.10) Q18 (02.00) Q19 (02.00) Q20 (140.00)