Concepts and Vocab
Gases are more compressible than solids and liquids because ____________.
In the gas phase, there is more space between individual particles.
What is the relationship (formula) between volume and temperature?
What is the combined gas law?
P1xV1/T1 = P2xV2/T2
Under which conditions do real gas particles behave like an ideal gas particle?
High temperature and low pressure
number of moles of gas
volume of gas
temperature of gas
What is the relationship (formula) between volume and pressure?
P1V1 = P2V2
P1 = 120kPa P2 = ?
V1 = 200mL V2 = 150mL
T1 = 310K T2 = 340K
175.5kPa
At 298K, the pressure of an ideal gas is 100kPa with a volume of 250L. How many moles of the ideal gas are present (R = 8.314)?
10 mol
n = 100 x 250 / 8.314 x 298
What are the standard temperature and pressure (STP)?
100kPa or 1atm
273K or 0oC
P1 = 136kPa P2 = ?
V1 = 5L V2 = 2L
340kPa
136 x 5 = 2 x ?
The volume of a gas-filled balloon is 30.0L at 333K and 143kPa. What would be the volume of the gas at STP?
35.2L
143 x 30 / 333 = 100 x ? / 273
A balloon is blown up with 250mL of helium (He) gas and 230kPa of pressure at 50oC. How many grams of helium were used to blow up the balloon (R = 8.314)?
0.086g He
273 + 50 = 323, 250mL = 0.25L
230kPa x 0.25L = n x 8.314 x 323K
n = 0.0214 mol x 4g/mol = 0.086g
What are the two units for pressure?
Pascals (Pa) or Kilopascals (kPa)
and
Atmospheres (atm)
A balloon inflated at 298K to 2.0L. After the balloon is heated to 360K, what will be the volume?
2.4L
2/298 = V2/360, V2= 2x360/298
At 300K, the pressure inside a nitrogen-filled tennis ball with a volume of 200L is 230kPa. How many moles of nitrogen gas are in the tennis ball (R=8.314)?
18.4 mol
230 x 200 = n x 8.314 x 300
An underground cavern with a volume of 700L contains 2.2x1025 molecules of oxygen (O2) and has a temperature 20oC. What is the pressure inside the cavern (R = 8.314)?
127.2kPa
20 + 273 = 293K, 2.2x1025 / 6.02x1023 = 36.54mol
P = 36.54 x 8.314 x 293 / 700
Volume and temperature are ____________ proportional.
Inversely
A sample of helium gas occupies a volume of 77mL at 148kPa. What is the pressure of the sample if the volume increases by 103mL?
63.3kPa
V2 = 77mL + 103mL = 180mL
77 x 148 = 180 x ?
The volume of a hot air balloon is 500.0 L at standard temperature and pressure. After the flame was ignited the gas was heated and the temperature increased by 200K, and the pressure increased by 100kPa. What will be volume of the gas?
433L
T2 = 273 + 200 = 473K
P2 = 100 + 100 = 200kPa
100 x 500 / 273 = 200 x ? / 473
A classroom holds 1 mole of air at STP, what is the volume of the gas in Liters (R = 8.314)?
22.4L
V = 1 x 8.314 x 273 / 100
1 mole = 22.4L