A 450 ml gas sample has a pressure of 1.25 atm at 65 °C. What is the temperature, in °C, at which the gas will expand to 865 mL with a pressure of 0.89 atm?

89°C

Explanation:

Combined Gas Law (P₁V₁)/T₁ = (P₂V₂)/T₂

(1.25 atm)(450 mL)/(65°C) = (0.89 atm)(865 mL)/T₂

8.653846154 = 769.85/T₂

T₂ = 769.85/8.653846154

T₂ = 88.96044444 = 89°C

the volume increases