The molar mass and the mass of the substance give the moles of the substance. The 10-gram sample of neon (Ne) has the fewest atoms. Thus, option b is correct.
<h3>What are moles?</h3>
Moles of the substance are the ratio of the molar mass and the mass of the substance. The moles of each atom with respect to the Avagadro's number (Nₐ) is given as,
Moles = mass ÷ molar mass
Moles of carbon (C) = 10 ÷ 12
= 0.83 Nₐ atoms
Moles of neon (Ne) = 10 ÷ 20
= 0.5 Nₐ atoms
Moles of fluorine (F) = 10 ÷ 19
= 0.52 Nₐ atoms
Moles of nitrogen (N) = 10 ÷ 14
= 0.7 Nₐ atoms
Moles of oxygen (O) = 10 ÷ 16
= 0.63 Nₐ atoms
Therefore, option b. 10 gm neon has the fewest atoms.