Chapter 12, Problem 1CQ

To determine

The heavier gas between one mole of $\text{Ne}$ gas, and one mole of ${\text{N}}_{\text{2}}$ gas.

Answer to Problem 1CQ

One mole of ${\text{N}}_{\text{2}}$ gas is heavier than one mole of $\text{Ne}$ gas.

Explanation of Solution

The mass number for Neon $\left(\text{Ne}\right)$ is $20$ and the mass number for nitrogen $\left({\text{N}}_{\text{2}}\right)$ is $14$ and is determined from the periodic table.

$\text{Ne}$ exists in atomic form as it is an inert gas. Therefore, one mole of $\text{Ne}$ gas weighs $20\text{g}$.

${\text{N}}_{\text{2}}$ gas contains nitrogen in molecular form. Therefore, one mole of nitrogen with two atoms of nitrogen weighs,

    $2\times 14\text{u}=28\text{u}$

Therefore, one mole of N₂ will have a mass of $28\text{g}$.

Conclusion

Therefore, one mole of N₂ gas is heavier than one mole of Ne gas.