8.98 dm3 of hydrogen gas is collected at 38.8 °C. Find the volume the gas will occup at -39.9 °C if the pressure remains constant.

V₂ = 6.7 dm³

Explanation:

Given data:

Volume of hydrogen = 8.98 dm³

Initial temperature = 38.8 °C

Final volume of hydrogen gas = ?

Final volume = -39.9°C

Solution:

Initial temperature = 38.8 °C (38.8 + 273 = 311.8 K)

Final volume = -39.9°C (-39.9 + 273 = 233.1 k)

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁  

V₂ = 8.98 dm³  × 233.1 K / 311.8 K

V₂ = 2093.238 dm³.K /311.8 K

V₂ = 6.7 dm³