Question

An ideal gas in a thermally insulated vessel at internal pressure = P₁, volume = V₁ and absolute temperature = T₁ expands irreversibly against zero external pressure, as shown in the diagram. The final internal pressure, volume and absolute temperature of the gas are P₂, V₂ and T₂, respectively. For this expansion,

(A) q = 0 

(B) T₂ = T₁ 

(C) P₂V₂ = P₁V₁ 

(D) P₂V₂ γ = P₁V₁ γ 

Answer 1

(A) q = 0 

(B) T₂ = T₁ 

(C) P₂V₂ = P₁V₁ 

Since container is thermally insulated. So, q = 0, and it is a case of free expansion therefore W = 0 and

ΔE = 0 

So, T₁ = T₂ 

Also, P₁V₁ = P₂V₂