Question

Exercise 5.38 Part A What is the volume occupied by 18.2 g of argon gas at a pressure of 1.14 bar and a temperature of 365 K? Express your answer with the appropriate units. THA O O ? V = 66.28 L Submit Previous Answers Request Answer X Incorrect; Try Again; One attempt remaining Part B Would the volume be different if the sample were 18.2 g of helium (under identical conditions)? The volume would be the lower for helium gas. The volume would be the greater for helium gas. The volume would be the same for helium gas. Submit Request Answer

Answer 1

A)

Molar mass of Ar = 39.95 g/mol

mass(Ar)= 18.2 g

use:

number of mol of Ar,

n = mass of Ar/molar mass of Ar

=(18.2 g)/(39.95 g/mol)

= 0.4556 mol

Given:

P = 1.14 bar

= (1.14/1.01325) atm

= 1.1251 atm

n = 0.4556 mol

T = 365.0 K

use:

P * V = n*R*T

1.1251 atm * V = 0.4556 mol* 0.08206 atm.L/mol.K * 365 K

V = 12.1289 L

Answer: 12.1 L

B)

Mass is same but due to different molar mas of He, the number of mol of He will be different and hence the volume would be different.

Molar mass is less for He.

So, number of mol will be more for He.

So, Volume would be more for He

Answer: option 2