The work done when 65.38g of zinc dissolved completely in HCl in an open beaker at 300k is

Zn + 2HCl → ZnCl2+H2 ↑No. of moles of Zn = No. of mole of H2 liberated=65.3865.38=1 mole                              VH2=nRTP=1×0.0821×3001 atm =24.63 lit w = - PΔV = - 1 atm [24.63-0]   = -24.63 x 101.3 J   = - 2495J