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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 of Fe is 55.85 u]
- 1
- 2
- 3
- 4
Correct answer: 4
Solution
The work done by the gas during expansion can be calculated using the formula W = PΔV. Given the reaction produces hydrogen gas, the amount of gas produced can be determined from the moles of iron reacting, leading to a specific volume change at constant pressure, which results in the work done being approximately 4 J.
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