Gases Quiz #2

A 7.50 liter sealed jar at 18 °C contains 0.250 moles of an unkown gas. What is the pressure in the container?

• 7.38 atm

• 0.796 atm

• 0.684 atm

• 0.398 atm

At 17 °C, a 0.80 mole sample of a gas exerts a pressure of 1.2 atmospheres. What is the volume of the container?

• 22.9 Liters

• 2355 Liters

• 0.0630 Liters

• 15.9 Liters

At what temperature (in Kelvin) would 4.0 moles of hydrogen gas in a 100 liter container exert a pressure of 1.00 atmospheres?

• 0.0305 K

• 0.487 K

• 32.8 K

• 304.5 K

What is STP?

• 1 Degrees Celsius and 0 ATM

• 0 Degrees Celsius and 1 ATM

• 0 Kevin and 10 ATM

• 273 Celsius and 273 ATM

When using the ideal gas law (PV=nRT), how does the type of gas being examined affect the outcome?

• It has no affect--the formula is a good approximation for all gases.

• You need to pay close attention to the type of gas--Helium and the Noble gases use a different equation

• Because each gas has a unique molecular mass, that difference needs to be accounted for.

• Using an isotope or an ion will change your results.

Shown below are four mercury barometers of the same height (all four barometer tubes measure one meter from the tube opening to rounded top). Which barometer shows the greatest external pressure?

• Barometer C

• Barometer D

• Barometer A

• Barometer B

Why does pressure increase when volume decreases

• When volume decreases, there are more collisions against the container

• When volume decreases, there are less collisions against the container

• When volume decreases, the particles move more quickly

• When volume decreases, the particles move less quickly

Why does pressure increase when the temperature increases

• When temperature increases, the particles increase in size

• When temperature increases, the particles decrease in size

• When temperature increases, the particles move more quickly

• When temperature increases, the particles move less quickly

Why does volume increase when the number of moles increases

• When the number of moles increases, there are more collisions against the container

• When the number of moles increases, there are more collisions against the container

• When the number of moles increases, they need to take up more space

• When the number of moles increases, they need to take up less space

Why does pressure decrease when the temperature decreases

• When temperature decreases, the particles increase in size

• When temperature decreases, the particles decrease in size

• When temperature decreases, the particles move more quickly

• When temperature decreases, the particles move less quick