At 25 ° C , 50 g of iron reacts with HCl to form FeCl 2 . 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 ]

Step-by-step solution

T = 298   K ,   R = 8 . 314   J molK → Chemical reaction is Fe 50 g + 2 HCl → FeCl 2 P = 1   bar + H 2 g = 50 55 . 85   mol → Work done for 1   mol gas = - P ext × ΔV = Δn g RT = - 1 × 8 . 314 × 298   J → Work done for 50 55 . 85 mol of gas = - 8 . 314 × 298 × 50 55 . 85   J = - 2218 . 059   J ≃ - 2218   J