A 3.68 L sample of methane gas is collected at 36.0 degrees C. Predict the volume of the sample at 0 degrees C.
To predict the volume of a gas sample at a different temperature, we can use the combined gas law, which states that the ratio of initial and final temperatures is equal to the ratio of initial and final volumes, assuming the pressure and number of moles remain constant.
The formula for the combined gas law is:
(P₁ * V₁) / T₁ = (P₂ * V₂) / T₂
Where:
P₁ and P₂ are the initial and final pressures (assuming they are the same, we can cancel them out),
V₁ and V₂ are the initial and final volumes,
T₁ and T₂ are the initial and final temperatures.
We are given:
V₁ = 3.68 L
T₁ = 36.0 degrees C = 36.0 + 273.15 = 309.15 K
T₂ = 0 degrees C = 0 + 273.15 = 273.15 K
Let's calculate V₂ using the formula:
(V₁ * T₂) / T₁ = (3.68 * 273.15) / 309.15 ≈ 3.25 L
Therefore, the predicted volume of the methane gas sample at 0 degrees C is approximately 3.25 L.
Remember to always convert temperatures to Kelvin when working with gas laws, as Kelvin is the absolute temperature scale used in these calculations.