Answer
1 - $NaHCO_3$
2 - $CO_2$
3 - $Ne$
Work Step by Step
1. Find the number of moles in 42g of $NaHCO_3$
- Molar Mass: 23 + 1 + 12 + (16*3) = 84g/mol
- n(moles) = $\frac{mass}{molarmass}$
- n(moles) = $\frac{42}{84}$ = 0.5 moles.
But, since there is 6 atoms for each molecule, the number of moles of atoms is 0.5 * 6 = 3
2. The number of moles of $CO_2$ is 1.5, therefore, the number of atom moles is 1.5 * 3 = 4.5.
3. Convert $6 \times 10^{24}$ atoms of $Ne$ into number of moles.
$n(atoms) = n(moles) * 6.0 \times 10^{23}$
$6 \times 10^{24} = n(moles) * 6.0 \times 10^{23}$
$n(moles) = \frac{6\times 10^{24}}{6\times 10^{23}} = 10$
Therefore, in order of increasing number of atoms, this samples are: $NaHCO_3$, $CO_2$ and $Ne$.