## Multiple Choice and Short Answer

Problem One

What pressure is necessary to increase the volume of 1.0 L of a gas at a pressure of 450 torr to a solume of 10 L?

Problem Two

A 1.0 L sample of a gas is at a pressure of 2 atmospheres. What volume will the sample have at a pressure of 1 atmosphere?

Problem Three

A 1.0 L sample of a gas is at a temperature of 273 K. What will the volume be if the temperature is increased to 546 K?

Problem Four

A 1.0 L sample of a gas is at a temperature of 25 °C and a pressure of 670 torr. If the volume is kept constant and the temperature is increased to 50 °C, what will the new pressure be?

Problem Five

A 1.0 L sample of a gas is at a temperature of 100 K and a pressure of 1.0 atm. If the temperature is increased to 200 K and the pressure is increased to 2.0 atm, what will the new volume be?

Problem Six

A 1.0 L sample of a gas is at a temperature of 100 K and a pressure of 0.50 atm. When the conditions are changed to STP, what is the new volume?

Problem Seven

A 1.0 L sample of a gas is at a temperature of 25 °C and a pressure of 670 torr. How many moles of the gas are present?

Problem Eight

A 2.8 g sample of N_{2} occupies a volume of 2.2 L at 0.0 °C. What is the pressure of the sample?

Problem Nine

A 2.8 g sample of a compound occupies a volume of 2.2 L at 0.0 °C and 1.0 atm. What is the molecular weight of the compound?

Problem Ten

A 0.10 g sample of N_{2} is present with 0.20 mole of O_{2}. The total pressure of the mixture is 1.0 atm. What is the partial pressure of O_{2}?

Problem Eleven

A sample of carbon dioxide has a volume of 200 mL at -10 °C and a pressure of 670 torr. What volume will the sample have at -10 °C and 230 torr?

Problem Twelve

A sample of carbon dioxide has a volume of 200 mL at -10 °C and a pressure of 670 torr. What volume will the sample have at 50 °C and 670 torr?

Problem Thirteen

A sample of carbon dioxide has a volume of 200 mL at -10 °C and a pressure of 670 torr. What volume will the sample have at 50 °C and 230 torr?

Problem Fourteen

A sample of carbon dioxide has a volume of 200 mL at -10 °C and a pressure of 670 torr. How many grams of carbon dioxide are present in the sample?

Problem Fifteen

What is the density of carbon dioxide at STP?

Problem Sixteen

What is the density of carbon dioxide at 500 torr and 50 °C?

Problem Seventeen

What volume of carbon dioxide will contain 6 x 10^{22} molecules at 500 torr and 50 °C?

Problem Eighteen

A sample of N_{2} occupies 500 mL at 25 °C and 350 torr. What pressure is required at a temperature of 100 °C to achieve a volume of 1000 mL?

Problem Nineteen

A 1.0 g sample of ethane (C_{2}H_{6}) occupies 1.0 L at a temperature of 25 °C. What is the pressure of the gas?

Problem Twenty

A gas has a density of 1.67 g/L at 35 °C and 700 torr. What is the molecular weight of the gas.

Problem Twenty One

A 0.450 g sample of a gas occupies 2.05 L at 0.0 °C and 0.5 atmospheres. What is the molecular weight of the gas?

Problem Twenty Two

The composition of air is approximately 21% oxygen, 78% nitrogen, and 1% argon. If the total pressure is 1.0 atmosphere, what is the partial pressure of argon?

Problem Twenty Three

If 1.6 g of methane (CH_{4}) at a pressure of 600 torr is collected over water at 25 °C, what volume is collected? [The vapor pressure of water at 25 °C is 25 torr.]

Problem Twenty Four

A classroom is 20 m long, 10 m wide, and 3 m high. The temperature is a balmy 30 °C and the relative humidity is 85%. How many grams of water are in the air? [Relative humidity is the ratio of the vapor pressure of water in the air to the vapor pressure of pure water. The vapor pressure of water at 30 °C is 32 torr.]