Question

A balloon filled with helium gas occupies 2.50 L at 25°C and 1.00 atm. When released, it rises to an altitude where the temperature is 20°C and the pressure is only 0.30 atm. Calculate the new volume of the balloon. Enter your answer in the box provided.

Answer 1

Answer:

8,19 L

Explanation:

The combined gas law is a equation that can be used when the initial and final conditions -pressure,volume,amount of moles,temperature-, of a gas change during a process. It can be written:

$\frac{P1V1}{n1T1}=\frac{P2V2}{n2T2}$

If the amount of the gas remains constant, then n1=n2 and we have:

$\frac{P1V1}{T1}=\frac{P2V2}{T2}$

For the problem we have:

Note: When working with gases is important to use absolute temperature values (°K, °K=°C+273,15):

P1=1 atm, V1=2,5L, T1=25+273,15=298,15°K

P2=0,3 atm, V2=?, T2=20+273,15=293,15°K

$V2=\frac{P1V1T2}{T1P2}=\frac{1atm*2,5L*293,15K}{298,15K*0,3atm}=8,19L$

The new volume of the balloon is 8,19 L.