At 10°C, the gas in a cylinder has a volume of 0.250 L. The gas is allowed to expand to 0.285 L. What must the final temperature be for the pressure to remain constant? (Hint °C + 273 = K.)

Use the formula: P1 V1 T1 = P2 V2 T2

We know that we want P1 = P2 so the pressure will remain constant, so we can say that: P1 V1 T1 = P1 V2 T2

Plug in the values we know: P1 ⋅0.250L 283K = P1 ⋅0.285L T2

(Remember that temperature must be done in Kelvin.)

Cross multiply: T2 ⋅ P1 ⋅0.250L=283K⋅ P1 ⋅0.285L

Divide both sides by P1.

T2 ⋅0.250L=283K⋅0.285L

T2 = 283K⋅0.285L 0.250L

T2 = 323K

(This is also 50˚C.)