Answer: The volume of given gas is 2.27 L.
Step-by-step explanation:
Given: Mass = 3.54 g
Temperature =
= (25 + 273) K = 298 K
Pressure = 725 mm Hg (1 mm Hg = 0.00131579) = 0.95 atm
As moles is the mass of substance divided by its molar mass.
So, moles of argon (molar mass = 40 g/mol) is as follows.

Formula used to calculate the volume of given gas is as follows.
PV = nRT
where,
P = pressure
V = volume
n = no. of moles
R = gas constant = 0.0821 L atm/mol K
T = temperature
Substitute the values into above formula as follows.

Thus, we can conclude that the volume of given gas is 2.27 L.