Question

If $10\text{g}$ of a molecule contains $1.505\times {10}^{22}$ molecules what will be the molar mass of the molecule?

• A. $400.13\text{g/mol}$
• B. $200.13\text{g/mol}$
• C. $300.42\text{g/mol}$
• D. $100\text{g/mol}$

Answer 1

The correct option is A $400.13\text{g/mol}$

Given,
The mass of $1.505\times {10}^{22}$ molecules = $10\text{g}$
So, the mass of $6.023\times {10}^{23}$ molecules $=\frac{10}{1.505\times {10}^{22}}\times 6.023\times {10}^{23}\text{g}$
$=400.13\text{g}$
Hence the molar mass of the gas molecule is $400.13\text{g/mol}$