At 25°C, 50 g of iron reacts with HCl to form FeCl2 . The evolved hydrogen gas expands against a constant pressure of 1 bar. The work done by the gas during this expansion is _______ J. (Round off to the Nearest Integer) [Given : R = 8.314 J mol-1 K-1. Assume, hydrogen is an ideal gas] [Atomic mass off Fe is 55.85 u]