Question

It is found that, when a dilute gas expands quasi-statically from 0.50 to 4.0 L, it does 250 J of work. Assuming that the gas temperature remains constant at 300 K, how many moles of gas are present?

(a) 0.1 mol
(b) 0.5 mol
(c) 1.0 mol
(d) 2.0 mol

Answer 1

To find the number of moles of gas present when it expands quasi-statically from 0.50 L to 4.0 L, we can use the ideal gas law equation. By rearranging the equation and substituting the given values, we find that there are 0.05 moles of gas present.

Step-by-step explanation:

To find the number of moles of gas present, we can use the ideal gas law equation:

PV = nRT

Where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature.

Since the gas expands quasi-statically, the change in volume (ΔV) is given as 4.0 L - 0.50 L = 3.5 L.

Given that the temperature remains constant at 300 K, we can rearrange the ideal gas law equation to solve for n:

n = PV / RT

Substituting the values into the equation:

n = [(1 atm)(3.5 L)] / [(0.08206 L·atm/mol·K)(300 K)]

Simplifying the equation gives:

n = 0.05 mol

Therefore, there are 0.05 moles of gas present.