Pressure of an ideal gas, contained in a closed vessel, is increased by 0.4% when heated by 1. Its initial temperature must be: (a) 2500 K (b) 25 (c) 250 (d) 250 K

Answer: (d). Closed vessel (constant V): P ∝ T ⇒ (Δ P)/(P) = (Δ T)/(T). 0.004 = 1/T ⇒ T = 250 K So the answer is (d) 250 K.

Pressure of an ideal gas, contained in a closed vessel, is increased… | JEE Main 2025 (3 Apr, Shift 2)

Q22JEE Main 2025 · 3 APR · SHIFT 2Easy

Gas Laws & Ideal Gas Equation

Pressure of an ideal gas, contained in a closed vessel, is increased by $0.4\%$ when heated by $1^\circ\text{C}$ . Its initial temperature must be:

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Answer: (d)

Closed vessel (constant $V$ ): $P \propto T \Rightarrow \dfrac{\Delta P}{P} = \dfrac{\Delta T}{T}$ .
$0.004 = \dfrac{1}{T} \Rightarrow T = 250$ K
So the answer is (d) 250 K.