Question

The molar mass of a certain gas is 49 g. What is the density of the gas in g/L at STP?

Answer 1

`\boxed{\text{2.2 g/L}}`

Step-by-step explanation:

We can use the Ideal Gas Law to calculate the density of the gas.

pV = nRT

n = m/M Substitute for n

pV = (m/M)RT Multiply both sides by M

pVM = mRT Divide both sides by V

pM = (m/V) RT

ρ = m/V Substitute for m/V

pM = ρRT Divide each side by RT

`\rho = (pM )/(RT)`

Data:

p = 1.00 bar

M = 49 g/mol

R = 0.083 14 bar·L·K⁻¹mol⁻¹

T = 0 °C = 273.15 K

Calculation:

ρ = (1.00 × 49)/(0.083 14 × 273.15) = 2.2 g/L

The density of the gas is
`\boxed{\text{2.2 g/L}}`.