Explanation:
According to the mole concept there are [tex]6.022 \times 10^{23}[/tex] atoms or molecules are present in 1 mole of a substance.
Mathematically, 1 mole = [tex]6.022 \times 10^{23}[/tex] atoms or molecules
Therefore, calculate the number of molecules present in 2.50 moles of [tex]H_{2}O[/tex] as follows.
[tex]2.50 mol \times 6.022 \times 10^{23}}molecules/mol[/tex]
= [tex]15.055 \times 10^{23}[/tex] molecules
Thus, we can conclude that there are [tex]15.055 \times 10^{23}[/tex] molecules in 2.50 moles of [tex]H_{2}O[/tex].
