Helmholtz free energy (A) is defined as

A. A = H - TS

B. A = E - TS

C. A = H + TS

D. None of these

Answer: Option B

Solution(By Examveda Team)

Helmholtz free energy :
\[\begin{array}{l} A = U - TS\\ dA = - {W_R} \end{array}\]
So, the decrease in Helmholtz energy denotes maximum work done in an reversible process under isothermal conditions.