1. q = 0, Δ T = 0 and w = 0 2. q = 0, Δ T 0 3. q 0, Δ T > 0 and w > 0

Answer: 1. q = 0, Δ T = 0 and w = 0 Free expansion means expansion into vacuum, so external pressure is zero and work w=-P_extΔ V=0 . Adiabatic means q=0 . Then Δ U=q+w=0 . For an ideal gas U depends only on temperature, so Δ T=0 . Hence q=0,\ Δ T=0,\ w=0 , option (1).

Topic: First law: work, heat, internal energy, enthalpy· Chemical Thermodynamics

The correct option for free expansion of an ideal gas under adiabatic condition is :

1. q = 0, \(\Delta\)T = 0 and w = 0

2. q = 0, \(\Delta\)T < 0 and w > 0

3. q < 0, \(\Delta\)T = 0 and w = 0

4. q > 0, \(\Delta\)T > 0 and w > 0

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Answer: 1. q = 0, \(\Delta\)T = 0 and w = 0

Free expansion means expansion into vacuum, so external pressure is zero and work \(w=-P_{ext}\Delta V=0\).

Adiabatic means \(q=0\). Then \(\Delta U=q+w=0\). For an ideal gas U depends only on temperature, so \(\Delta T=0\).

Hence \(q=0,\ \Delta T=0,\ w=0\), option (1).

Doubtly AI · 30 Oct 2026 AI-generated · not yet verified Report

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The correct option for free expansion of an ideal gas under adiabatic condition is :

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