Explanation:
As per the mole concept, there are \(6.022 \times 10^{23} atoms\) present in 1 mole of a substance.
Mathematically, 1 mole = \(6.022 \times 10^{23}\) atoms or molecules
Therefore, number of moles of oxygen atoms present in \(3.98 \times 10^{23}\) atoms are calculated as follows.
\(\frac{3.98 \times 10^{23} atoms}{6.022 \times 10^{23}atoms/mol}\)
= 0.66 mol
Thus, we can conclude that there are 0.66 moles of oxygen atoms are in a sample of \(3.98 \times 10^{23} atoms\).
