An expandable balloon volume calculation
An expandable balloon contains 3.50 dm3 of helium at 101. kPa and 23.0oC.
What volume will the balloon occupy when the pressure drops to 85.0 kPa and the temperature is 10.0oC?
Answer:
3.98dm³
Explanation:
Using combined gas law equation:
P1V1/T1 = P2V2/T2
Where;
P1 = initial pressure (kPa)
P2 = final pressure (kPa)
V1 = initial volume (dm³)
V2 = final volume (dm³)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the provided information in this question:
V1 = 3.5dm³
V2 = ?
P1 = 101 kPa
P2 = 85.0 kPa
T1 = 23.0°C = 23 + 273 = 296K
T2 = 10.0°C = 10 + 273 = 283K
Using P1V1/T1 = P2V2/T2
101 × 3.5/296 = 85 × V2/283
353.5/296 = 85V2/283
Cross multiply
296 × 85V2 = 353.5 × 283
25,160V2 = 100,040.5
V2 = 100,040.5 ÷ 25,160
V2 = 3.98dm³