0.820 mole of hydrogen gas has a volume of 2.00 L at a certain temperature and pressure. What is the volume of 0.125 mol of this gas at the same temperature and pressure
A) 0.0512 L
B) 0.250 L
C) 0.305 L
D) 4.01 L
E) 19.5 L

Question

Quizplus · Accepted Answer

According to the ideal gas law, 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 temperature and pressure are constant, we can write:

PV/n = constant

Therefore, for a given gas at two different amounts (moles) but under the same conditions, we have:

(PV)/n = constant

PV = k (where k is a constant)

Thus, we can set up the following equation to solve for the volume of 0.125 moles of hydrogen gas:

(2.00 L)(0.820 mol) = V(0.125 mol)

V = (2.00 L)(0.820 mol) / 0.125 mol

V = 13.04 L / mol

V = 0.305 L

Therefore, the volume of 0.125 mol of hydrogen gas at the same temperature and pressure is 0.305 L, which is choice C.

0820 Mole of Hydrogen Gas Has a Volume of 2