The general gas energy equation is (where Q1 – 2 = Heat supplied, dU = Change in internal energy, and W1 – 2 = Work done in heat units)

The general gas energy equation is (where Q_{1 – 2} = Heat supplied, dU = Change in internal energy, and W_{1 – 2} = Work done in heat units)

(A) Q_{1 – 2} = dU + W_{1 – 2}                   (Ans)

(B) Q_{1 – 2} = dU – W_{1 – 2}

(C) Q_{1 – 2} = dU/W_{1 – 2}

(D) Q_{1 – 2} = dU × W_{1 – 2}