What change in volume results if 80.0 mL of gas is cooled from 84 °C to 57.0 °C?

73.95 mL.

Explanation:

We can use the general law of ideal gas: PV = nRT.

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R is the general gas constant,

T is the temperature of the gas in K.

If n and P are constant, and have two different values of V and T:

V₁T₂ = V₂T₁

V₁ = 80.0 mL, T₁ = 84.0°C + 273 = 357.0 K.

V₂ = ? mL, T₂ = 57.0°C + 273 = 330.0 K.

∴ V₂ = V₁T₂/T₁ = (80.0 mL) (330.0 K) / (357.0 K) = 73.95 mL.