Boyle's/Charles'/Gay Lussac/ Combined Gas Laws
What happens to the volume of a gas if you double the pressure?
The volume will be halved
Which of the following represents the smallest gas pressure?
1.8 psi
1.8 Torr
1.8 atm
1.8 kPa
1.8 bar
1.8 Torr
Name the four variables included in the ideal gas law.
n = number of moles
T = temperature
P = pressure
V = volume
What volume does 1 mole of any gas occupy at STP?
22.4 L
What are the values of STP?
0 0C and 1 atm
If 3.0 L of He at 200C is allowed to expand to 4.4 L, what is the new temperature (in 0C)?
157 0C
What quantity is represented by each of the following:
1 atm = ___ Torr = ____mmHg=____psi
760 Torr, 760 mmHg, 14.7 psi
The nitrogen gas in an air bag has a volume of 65 L and exerts a pressure of 829 mmHg at 25 0C. How many moles of nitrogen are in the air bag?
2.9 moles
At STP, 15 L of N2 are reacted with excess H2. How many grams of NH3 are produced?
___N2 + ____H2 -----> ____ NH3
22.8 g NH3
Name the gases:
1. Used as a chemical weapon in WWI
2. Most dense noble gas
3. Most common gas in atmosphere
4. Most reactive elemental gas
1. Chlorine
2. Radon
3. Nitrogen
4. Fluorine
An air compressor reduced a sample of H at 250C and 740 Torr to 6.75 L at 42 atm and 85 0C. What was the original volume of the gas?
242 L
Which of the following represents the largest gas pressure?
5 Torr, 5 mmHg, 5 atm, 5 kPa, 5 psi
5 atm
A mixture of gases contains 0.31 moles CH4, 0.25 moles H2, and 0.29 moles O2. What is the volume of the mixture of gases at STP?
19.04 L
If 25 g of S is reacted with excess O2, what volume of SO2 can be produced at STP?
_____S + ____ O2 ------> _____ SO2
17.49 L
Name the three most abundant gases in air.
N2, O2, Ar
all <0.05% = CO2, Ne, He, Kr, Xe, O3, CH4
H2O vapor varies by location
A gas in a rigid container is cooled from 500 K to 100 K. By what factor does the pressure in the container change? (be specific)
It is reduced by a factor of 5 or 1/5 the original pressure
Rank 355 Torr, 0.534 atm, and 100 kPa in increasing order of pressure
355 Torr < 0.534 atm < 100 kPa
H2 is collected by water displacement. At 300C and 988 mmHg you collect 600 mL. What is the mass of H2 obtained.
0.063 g H2
If 40 L of N2 is produced at STP, how much NaN3 was originally used?
____ NaN3 -----> ____ Na + ____ N2
77.40 g NaN3
Describe the tests and results expected to determine whether the gas you collected is CO2, H2, or O2
CO2 = puts burning splint out
H2= burns fast and with a "bark"
O2= makes a glowing splint relight and a burning splint with burn brighter
Calculate the volume of 88.4 g of CO2 at STP.
45 L
What is the value of R, the universal gas constant, as well as its correct units?
0.0821 atm L/mol K
At STP, 0.280 L of a gas weighs 0.400 g. Calculate the molar mass of the gas.
32.0 g/mole
How many molecules of NH3 are produced from the reaction of 3.0 L of N2 and 3.0 L of H2 at STP?
_____ N2 + _____ H2 -------> _____ NH3
5.38 x 1022 molecules of NH3
You have 10 moles of He at STP. What many liters is this?
22.4(10) = 224 L