A 0.0125-g sample of a gas with an empirical formula of CHF2 is placed in a 165-mL flask. It has a pressure of 13.7 mm Hg at 22.5 °C. What is the molecular formula of the compound?

You have two pressure-proof steel cylinders of equal volume, one containing 1.0 kg of CO and the other containing 1.0 kg of acetylene, C2H2. (a) In which cylinder is the pressure greater at 25 C? (b) Which cylinder contains the greater number of molecules?

47 HCl(g) reacts with ammonia gas, NH3(g), to form solid ammonium chloride. If a sample of ammonia occupying 250 mL at 21 C and a pressure of 140 torr is allowed to react with excess HCl, what mass of NH4Cl will form?

You have a 550.-mL tank of gas with a pressure of 1.56 atm at 24 C. You thought the gas was pure carbon monoxide gas, CO, but you later found it was contaminated by small quantities of gaseous CO2 and O2. Analysis shows that the tank pressure is 1.34 atm (at 24 C) if the CO2 is removed. Another experiment shows that 0.0870 g of O2 can be removed chemically. What are the masses of CO and CO2 in the tank, and what is the partial pressure of each of the three gases at 25 C?