Question

Hydrogen gas has a density of 0.090 g/L, and at normal pressure and -1.72 °C one mole of it takes up 22.4 L.
How would you calculate the moles in 900.0 g of hydrogen gas? Set up the math. Just leave your answer as a math expression.

Answer 1

Answer: The number of moles of given amount of hydrogen gas is $x=\frac{900.0g}{2g/mol}$

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

We are given:

Let the number of moles of hydrogen gas be 'x'

Given mass of hydrogen gas = 900.0 g

Molar mass of hydrogen gas = 2 g/mol

Putting values in above equation, we get:

$x=\frac{900.0g}{2g/mol}=450mol$

Hence, the number of moles of given amount of hydrogen gas is $x=\frac{900.0g}{2g/mol}$