The density of an ideal gas at STP is found to be 1.41 g/L. What is its molar mass?

Ethanol, C2H5OH, is produced industrially from ethylene, C2H4, by the following sequence of reactions: 3C2H4+2H2SO4C2H5HSO4+( C 2 H 5)2SO4C2H5HSO4+( C 2 H 5)2SO4+3H2O3C2H5OH+2H2SO4 What volume of ethylene at STP is required to produce 1.000 metric ton (1000 kg) of ethanol if the overall yield of ethanol is 90.1%?

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?

54 One way to generate oxygen is to heat potassium chlorate, KClO3. (The other product is potassium chloride.) If 386 mL of oxygen at 41 C and 97.8 kPa is generated by this reaction, what is the minimum mass of KClO3used?

Consider the following sketch. Each square in bulb A represents a mole of atoms X. Each circle in bulb B represents a mole of atoms Y. The bulbs have the same volume, and the temperature is kept constant. When the valve is opened, atoms of X react with atoms of Y according to the following equation: 2X(g)+Y(g)X2Y(g)The gaseous product is represented as and each represents one mole of product. (a) IfP A=2.0 atm, what is P8 before the valve is opened and the reaction is allowed to occur? What is P A+P B? (b) Redraw the sketch to represent what happens after the valve is opened. (c) What is PA? What is PB? What is P A+P B? Compare your answer with the answer in part (a).

perform stoichiometric ca1cu1uions for reactions involving gases as reactants or products.

Liquid oxygen was first prepared by heating potassium chlorate, KClO3, in a closed vessel to obtain oxygen at high pressure. The oxygen was cooled until it liquefied. 2KClO3(s)2KCl(s)+3O2(g) If 171 g of potassium chlorate reacts in a 2.70-L vessel, which was initially evacuated, what pressure of oxygen will be attained when the temperature is finally cooled to 25C? Use the preceding chemical equation and ignore the volume of solid product.

Pressures of gases in mixtures are referred to as partial pressures and are additive. 1.00 L of He gas at 0.75 atm is mixed with 2.00 L of Ne gas at 1.5 atm at a temperature of 25.0 C to make a total volume of 3.00 L of a mixture. Assuming no temperature change and that He and Ne can be approximated as ideal gases, what are a the total resulting pressure, b the partial pressures of each component, and c the mole fractions of each gas in the mix?

A 275-mL sample of CO gas is collected over water at 31C and 755 mmHg. If the temperature of the gas collection apparatus rises to 39C, what is the new volume of the sample? Assume that the barometric pressure does not change.

105 The decomposition of mercury(II) thiocyanate produces an odd brown snake-like mass that is so unusual the process was once used in fireworks displays. There are actually several reactions that take place when the solid Hg(SCN)2 is ignited: 2Hg(SCN)2(s)2HgS(s)+CS2(s)+C3N4(s)CS2(s)+3O2(g)CO2(g)+2SO2(g)2C3N4(s)3(CN)2(g)+N2(g)HgS(s)+O2(g)Hg(l)+SO2(g) A 42.4-g sample of Hg(SCN)2 is placed into a 2.4-L vessel at 21°C. The vessel also contains air at a pressure of 758 torr. The container is sealed and the mixture is ignited, causing the reaction sequence above to occur. Once the reaction is complete, the container is cooled back to the original temperature of 21°C. (a) Without doing numerical calculations, predict whether the final pressure in the vessel will be greater than, less than, or equal to the initial pressure. Explain your answer. (b) Calculate the final pressure and compare your result with your prediction. (Assume that the mole fraction of O2 in air is 0.21.)