Tiêu đề DPP-6 SOLUTION.pdf ✅

3 (a) Number of octahedral sites = Number of sphere in the packing ∴ Number of octahedral sites per sphere = 1 4 (b) One gram mole of a gas at NTP occupies 22.4 L as volume. This fact was derived from Avogadro’s hypothesis 6 (c) In ideal gas equation the value of universal gas constant depends on the units of the measurement. Numerical values of R, (a) 0.0821 L atm K ―1 mol―1 (b) 8.314 J K ―1 mol―1 (c) 8.314 × 107 erg K ―1 mol―1 7 (c) These are facts about Loschmidt’s number. 8 (c) According to Boyle’s law V = K P 9 (d) Effusion does not depend on size of the molecule 10 (b) According to Graham’s law of diffusion r ∝ 1 M The rate of diffusion of ammonia (M = 17) is more than the HCl (M = 36.5), thus white ring forms near the hydrogen chloride bottle 12 (a) Frenkel’s defect is due to shift of an ion from the normal lattice site (creating a vacancy) and occupy interstitial spaces 14 (a) KE = 3 2 RT for 1 mole of gas ∆KE = 3 2 × 8.315 × (50 ― 0) = 3 2 × 8.315 × 50 = 623.25 J 15 (b) From the total pressure and the vapour pressure of water, we can calculate the partial
pressure of O2 pO2 = pT ― pH2O = 760 ― 22.4 = 737.6 mm Hg From the ideal gas equation we write m = pVM RT = 0.974 × 0.128 × 32.0 0.0821 × 297 = 0.163 g 16 (a) Lowering of temperature decreases kinetic energy and increase of pressure increases forces of attractions. 17 (a) We know that, Vrms = 3RT M So, as the molecular mass increases, rms speed decreases. Thus, the correct order of root mean square speed is H2 > N2 > O2 > HBr 18 (b) r1 r2 = 1 6 = [ M2 M1 ] = 2 M ∴ M = 72 19 (a) uAV ∝ [ 8RT πM ] or u ∝ [ T M ]
ANSWER-KEY Q. 1 2 3 4 5 6 7 8 9 10 A. C C A B A C C C D B Q. 11 12 13 14 15 16 17 18 19 20 A. A A D A B A A B A D