Question

Define Extensive property. Calculate the work done during the expansion of 2 moles of an ideal gas from 10 dm^3 to 20 dm^3 at 298 K in vacuum.

Hint:

Work is only done when there is an opposing pressure. In a vacuum, there is no external pressure, so the work done by the gas is zero.

Answer 1

1. Extensive Property: An extensive property is a physical property that depends on the amount or size of the substance in the system. Examples include mass, volume, and energy. These properties change as the size or amount of material in the system changes. 2. Work Done by the Gas: The work done by an ideal gas during expansion or compression is given by the formula: \[ W = -P \Delta V \] Where: - \( W \) is the work done by the gas. - \( P \) is the pressure of the gas (which is constant in this case since it's a vacuum). - \( \Delta V \) is the change in volume. Since the expansion occurs in vacuum, there is no external pressure opposing the expansion (\( P = 0 \)). Thus, the work done is: \[ W = 0 \times (V_f - V_i) = 0 \] Thus, the work done during the expansion is: \[ \boxed{0} \]