When 1 mol of gas expands from a volume of 2.5 dm³ to 5 dm³ against a constant pressure of 1 atm, calculate the energy transferred as work, w, (in J).

Question

Quizplus · Accepted Answer

The work done by the gas is given by the equation:

w = -PΔV

where P is the pressure, and ΔV is the change in volume.

In this case, P = 1 atm and ΔV = 5 dm3 - 2.5 dm3 = 2.5 dm3.

Substituting these values into the equation, we get:

w = -(1 atm)(2.5 dm3) = -2.5 L atm

To convert from L atm to Joules, we use the conversion factor:

1 L atm = 101.325 J

Therefore,

w = -2.5 L atm × 101.325 J/L atm = -253 J

The negative sign indicates that work is done on the system (the gas) by the surroundings (the constant pressure). Therefore, the best choice is C, which is the only negative option.

When 1 Mol of Gas Expands from a Volume of 2.5