Question

Calculate the volume of each gas sample at STP.

Part A 51.1 g He Part B 47.0 g Xe Part C 49.6 mg Cl2 Part D 3.82 kg SO2.

Answer 1

A)

Molar mass of He = 4.003 g/mol

mass(He)= 51.1 g

use:

number of mol of He,

n = mass of He/molar mass of He

=(51.1 g)/(4.003 g/mol)

= 12.77 mol

Given:

P = 51.1 atm

n = 12.7654 mol

T = 273.0 K

use:

P * V = n*R*T

51.1 atm * V = 12.7654 mol* 0.08206 atm.L/mol.K * 273 K

V = 5.5964 L

Answer: 5.60 L

B)

Molar mass of Xe = 131.3 g/mol

mass(Xe)= 47.0 g

use:

number of mol of Xe,

n = mass of Xe/molar mass of Xe

=(47 g)/(1.313*10^2 g/mol)

= 0.358 mol

Given:

P = 51.1 atm

n = 0.358 mol

T = 273.0 K

use:

P * V = n*R*T

51.1 atm * V = 0.358 mol* 0.08206 atm.L/mol.K * 273 K

V = 0.1569 L

Answer: 0.157 L

C)

Molar mass of Cl2 = 70.9 g/mol

mass(Cl2)= 49.6 mg

= 0.0496 g

use:

number of mol of Cl2,

n = mass of Cl2/molar mass of Cl2

=(4.96*10^-2 g)/(70.9 g/mol)

= 6.996*10^-4 mol

Given:

P = 51.1 atm

n = 6.996*10^-4 mol

T = 273.0 K

use:

P * V = n*R*T

51.1 atm * V = 6.996*10^-4 mol* 0.08206 atm.L/mol.K * 273 K

V = 3.07*10^-4 L

Answer: 3.07*10^-4 L

D)

Molar mass of SO2,

MM = 1*MM(S) + 2*MM(O)

= 1*32.07 + 2*16.0

= 64.07 g/mol

mass(SO2)= 3.82 Kg

= 3820.0 g

use:

number of mol of SO2,

n = mass of SO2/molar mass of SO2

=(3.82*10^3 g)/(64.07 g/mol)

= 59.62 mol

Given:

P = 51.1 atm

n = 59.6223 mol

T = 273.0 K

use:

P * V = n*R*T

51.1 atm * V = 59.6223 mol* 0.08206 atm.L/mol.K * 273 K

V = 26.1386 L

Answer: 26.1 L