Question

The percentage rise in temperature needed to expand a gas by 40% at constant pressure is______.​

Answer 1

The percentage rise in temperature needed to expand a gas by 40% at constant pressure is ..

solution : let initial volume of gas is V

after expansion of gas, volume of gas will be , $V_f$ = V + 40% of V = 1.4V

at constant pressure, the volume of gas is directly proportional to the temperature. it is also known as Charle's law.

i.e., V ∝ T

⇒ V₁/V₂ = T₁/T₂

⇒ V₂/V₁ = T₂/T₁

⇒ (V₂ - V₁)/V₁ = (T₂ - T₁)/T₁

⇒ (1.4V - V)/V = ΔT/T₁

⇒ 0.4V/V × 100 = ΔT/T₁ × 100 = the percentage change in the temperature.

⇒ the percentage change in the temperature = 40%

therefore the rise in the temperature is also by 40%. if gas expands by 40%.