A sample of 0.02 mol of chlorine gas is kept at 27 degrees C and 0.15 atm. What would be its pressure if the temperature was increased to...?

Initial: P₁ = 0.15 atm, T₁ = (273 + 27) K = 300 K
Final: P₂ = ? atm, T₂ = (273 + 227) K = 500 K

For a fixed amount of gas (0.02 mol) with constant volume : P₁/T₁ = P₂/T₂
Final pressure, P₂ = P₁ × (T₂/T₁) = (0.15 atm) × (500/300) = 0.25 atm