A sample of nitrogen gas has a volume of 150.0 mL at STP. What volume does the gas occupy if the absolute temperature and pressure are each tripled? a. 450.0 mL
b. 50.00 mL
c. 150.0 mL
d. 500.0 mL
e. 67.20 L
Explanation: STP stands for standard temperature and pressure. Standard temperature is 273 K and standard pressure is 1 atm. We are also given the volume. We need to use combined gas law to determine the new volume once the temperature and pressure are tripled. The combined gas law is P1V1/T1 = P2V2/T2
P1 = 1atm
V1 = 150.0 ml
T1 = 273 K
P2 = 3atm
V2 = ?
T2 = 273 K*3 = 819K
Let's now plug into the formula, we get:
(1atm)(150.0 ml)/ 273 K = 3atm (V2)/819K
V2 = 150.0 ml
Alternatively, notice that volume is in the numerator and temperature in the denominator. If we do the same thing to both, then the answer should be unchanged.
Answer: c