AP Chemistry Unit 3

mole of He was placed in each flask. Which statement is true?

• Since all flask have same amount of gas, flask 1 has the least pressure

• Since all flask have same amount of gas, flask 2 has the least pressure

• Since all flask have same amount of gas, flask 3 has the least pressure

• Since all flask have same amount of gas, flask 4 has the least pressure

Compressing a gas makes the pressure _______.

• increase

• decrease

• stay the same

• I don't know

Two sealed, rigid 5.0L containers each contain a gas at the same temperature but at a different pressure, as shown above. Also shown are the results of transferring the entire contents of container 1 to container 2. No gases escape during the transfer. Assuming ideal behavior, which statement is correct regarding the total pressure of the gases after they are combined?

• The total pressure of the gases in the mixture is the sum of the initial pressures of oxygen gas and nitrogen gas because pressure only depends on the total amount of gas when volume and temperature are held constant.

• The total pressure of the gases in the mixture is lower than the sum of the initial pressures of oxygen and nitrogen because some of the energy of the particles will be lost due to an increase in the number of collisions.

• The total pressure of the gases in the mixture is higher than the sum of the initial pressures of oxygen and nitrogen because of the intermolecular forces that develop between oxygen and nitrogen molecules.

• The total pressure of the gases in the mixture cannot be determined because the actual value of the temperature is not given.

In general, substances with stronger intermolecular forces have ________ boiling points than those with weaker forces

• Higher

• Lower

• Forces and boiling point are not related

A sealed vessel contains 0.200 mol of oxygen gas, 0.100 mol of nitrogen gas, and 0.200 mol of argon gas. The total pressure of the gas mixture is 5.00 atm. The partial pressure of the argon is

• 0.200 atm

• 0.500 atm

• 1.00 atm

• 2.00 atm

At an ocean depth of 10.0 m, a diver’s lung capacity is 2.40 L. The air temperature is 32.0°C and the pressure is 101.30 kPa. What is the volume of the diver’s lungs at the same depth, at a temperature of 21.0°C and a pressure of 141.20 kPa?

• 1.12 L

• 1.66 L

• 1.78 L

• 4.86 L

What volume does .0685 mol of gas occupy at STP?

• 0.3707 mol

• 0.7515 mol

• 1.53 L

• 3.06 L

Calculate the molar mass of a gaseous substance if 0.125 g of the gas occupies 93.3 mL at STP.

• 30.0 g/mol

• 30.2 g/mol

• 30.4g/mol

• 30.6 g/mol

• None of the above

The force of attraction between nonpolar molecules:

• Hydrogen Bonding

• Dipole - Dipole Forces

• LDF

• Ionic Forces

Which of these is not an intermolecular force?

• covalent bonding

• hydrogen bonding

• London dispersion forces

• dipole-dipole forces