164) 0.553 gm of a Boron−Hydrogen compound created a pressure of 0.658 atm in a bulb of 407 mL at 373 K. If the compound has 85.7% boron, what will be the molecular formula of the compound?

165) 4 gm of argon in a bulb at a temperature of T K, had a pressure P atm. When the bulb was placed in hotter bath at a temperature 50^o more than the first one, 0.8 gm of gas had to be removed to get the original pressure. T is equal to:

166) The vapour pressure of water at 20^oC is 17.5 torr. What will be the number of moles of water present in 1 L of air at 20^oC and 40% relative humidity?

167) 1 mol each of a monoatmoic, diatomic and triatomic gases are mixed. C_p⁄C_v for the mixture is:

168) An LPG cylinder contains 15 kg of butane gas at 27^oC and 10 atm pressure. It was leaking and its pressure fell down to 8 atm after 1 day. The gas leaked in 5 days is: