Exam 5: Gases

The mole fraction of oxygen molecules in dry air is 0.2095.What volume of dry air at 1.00 atm and 25°C is required for burning 1.00 L of octane (C₈H₁₈, density = 0.7025 g/mL)completely, yielding carbon dioxide and water?

If equal masses of O₂(g)and HBr(g)are in separate containers of equal volume and temperature, which one of these statements is true?

Many automobiles produce about 5 grams of NO for each mile they are driven.How many liters of NO gas at STP would be produced on a 100-mile trip?

A spacecraft is filled with 0.500 atm of O₂ and 0.500 atm of He.If there is a very small hole in the side of this craft such that gas is lost slowly into outer space,

In an effort to address concerns about global warming, a power plant in Portland,Oregon is designed to take all of its exhaust gases from its boilers and recycle the CO₂ using the Solvay process to make sodium hydrogen carbonate.The reaction is shown below. NH₃(g)+ H₂O(l)+ CO₂(g)+ NaCl(aq) $\rarr$ NaHCO₃(aq)+ NH₄Cl(aq) How many liters each of NH₃ and CO₂ (both at STP)would be consumed to produce 3.00 kg of sodium bicarbonate?

If the pressure on a gas sample is tripled and the absolute temperature is quadrupled, by what factor will the volume of the sample change?

Gasoline (which can be considered to be octane, C₈H₁₈)burns in oxygen to produce carbon dioxide and water.What volume (L)of carbon dioxide at STP is generated as a result of the combustion of 1.0 gal of gasoline? (The density of gasoline is 0.81 g/mL.1 gal = 3.78 L)

A sample of oxygen gas has a volume of 545 mL at 35°C.The gas is heated to 151ºC at constant pressure in a container that can contract or expand.What is the final volume of the oxygen gas?

Calculate the density of CO₂(g)at 120°C and 790 mmHg pressure.

What is the significance of the magnitude of the van der Waals "a" constant?

A sample of mercury(II)oxide is placed in a 5.00 L evacuated container and heated until it decomposes entirely to mercury metal and oxygen gas.The container is then cooled to 25°C.One now finds that the gas pressure inside the container is 1.73 atm.What mass of mercury(II)oxide was originally placed into the container?

Gas A and gas B are combined in a flask at initial pressures of 1.0 atm each.The flask is sealed and over time they react to completion to give gas C according to the following chemical equation: 2A(g)+ B(g) $\rarr$ C(g) Assuming the temperature stays constant, what will be the total pressure in the flask after the reaction goes to completion?

What mass of KClO₃ must be decomposed to produce 126 L of oxygen gas at 133°C and 0.880 atm? (The other reaction product is solid KCl.)

Define Boyle's Law

How many grams of N₂O, nitrous oxide, are contained in 500.mL of the gas at STP?

Packaged cake mixes usually contain baking powder, a mixture of sodium hydrogen carbonate and calcium hydrogen phosphate that react to produce carbon dioxide gas when they are heated in water.The CO₂(g)formed allows the cake to "rise." When such cake mixes are used at high altitudes, often the cake will rise too much and collapse, unless special instructions are followed.Why does this happen?

A method of removing CO₂ from a spacecraft is to allow the CO₂ to react with sodium hydroxide.(The products of the reaction are sodium carbonate and water.)What volume of carbon dioxide at 25°C and 749 mmHg can be removed per kilogram of sodium hydroxide that reacts?

Define Avogadro's Law

Samples of the following volatile liquids are opened simultaneously at one end of a room.If you are standing at the opposite end of this room, which species would you smell first? (Assume that your nose is equally sensitive to all these species.)

Calculate the density of Ar(g)at -11°C and 675 mmHg.