A sample of gas at a constant temperature has an initial pressure of at a pressure of . If the volume of gas is decreased to , what is its pressure?

Suppose that hydrochloric acid and aluminum are reacted to produce hydrogen gas. This hydrogen gas is collected by displacement of water at and a total pressure of . If the volume of the gas collected is , then how many moles of hydrogen were collected?

Note: The vapor pressure of water at is .

A 4.0 L container at 25 C is filled with 2.0 g neon and 8.0 g helium. What is the total pressure of the mixture?

Suppose a source of water is boiling. If the ambient pressure above the surface of the water were to increase, which of the following would happen to the boiling water?

Ice cubes are dropped into a glass of water. You notice that the glass of water becomes colder and condensation appears. Later in the day, you notice the glass of water is now room temperature and there is no more condensation. Which of the following concepts describes this process?

Use average bond enthalpies to estimate the enthalpy change, in kilojoules, of the combustion of one mole of hexane to form liquid water and carbon dioxide gas.

Type of Bond	Average bond enthalpy
Carbon-hydrogen single bond	414
Carbon-oxygen double bond	736
Oxygen-oxygen double bond	498
Oxygen-hydrogen single bond	464
Carbon-carbon single bond	347

A block of silver initially at absorbs of heat. If the specific heat capacity of silver is , in degrees Celsius, what is the final temperature of the block of silver?

Which of the following is true of a closed system?

One flask is at STP and another is at . What is the pressure at ?

Suppose that hydrochloric acid and aluminum are reacted to produce hydrogen gas. This hydrogen gas is collected by displacement of water at and a total pressure of . If the volume of the gas collected is , then how many moles of hydrogen were collected?

Note: The vapor pressure of water at is .