Question

The molar mass of an unknown gas was measured by an effusion experiment. It was found that it took 63 s for the gas to effuse, whereas nitrogen gas (N2) required 48 s. The molar mass of the unknown gas is-

Answer 1

8.13 g/mol.

Step-by-step explanation:

The following formula gives us the relationship between the effusion rates of two gases and their molar masses:

`\sqrt{(MM_(x) )/(MM_(y) ) } = (rate_(y) )/(rate_(x) )`

where x and y are respective sample gases and MM and rate are molar mass and rate of effusion respectively.

⇒
`\sqrt{(14)/(y) } = (63)/(48)`

`(14)/(y) = 1.3125^(2)`

y= 14 /
`1.3125^(2)` = 8.13 g/mol.