Chemistry - Ideal Gas Question with Solution | TestHub
A closed rigid bulb contains 0.01 mole of inert helium gas and a sample of solid white ammonium chloride, NH₄Cl. Assume that the volume of the solid NH₄Cl is negligible compared to the volume of the bulb. The pressure of He is measured at 300 K and is found to be 78 mm Hg. The bulb is then heated to 600 K. All the NH₄Cl decomposes to NH₃(g) and HCl(g). The final total pressure in the bulb after complete decomposition of the solid is 468 mm Hg. Assume ideal behaviour for all gases.
The approximate mass of NH₄Cl present initially in the bulb is
Options:
Answer:
Solution:
At 600 K, He alone gives 78 × 600/300 = 156 mm Hg. So p(NH₃) + p(HCl) = 468 - 156 = 312 mm, i.e. p(NH₃) = 156 mm. n(NH₃) = (156 × 2.4)/(62.4 × 600) = 0.01 mol. Mass of NH₄Cl = 0.01 × 53.5 = 0.535 g. Hence (c).
