Explanation:
According to the mole concept, there are [tex]6.022 \times 10^{23}[/tex] atoms or molecules present in 1 mole.
As, it is given that mass of ethyne is 84.3 g. Hence, calculate its number of moles as follows.
No. of moles = [tex]\frac{mass}{\text{molar mass}}[/tex]
= [tex]\frac{84.3 g}{26.04 g/mol}[/tex]
= 3.24 mol
Therefore, calculate number of ethyne molecules as follows.
[tex]3.24 mol \times 6.022 \times 10^{23}[/tex] atoms
= [tex]19.51 \times 10^{23}[/tex] atoms
Thus, we can conclude that there are [tex]19.51 \times 10^{23}[/tex] atoms in 84.3 grams of ethyne.
