Answer: There are 14.152 molecules in 42.3 g sample of water, [tex]H_{2}O[/tex].
Explanation:
According to the mole concept, 1 mole of every substance contains [tex]6.022 \times 10^{23}[/tex] atoms.
As mass of water (molar mass = 18 g/mol) is given as 42.3 g. Therefore, moles of water are as follows.
[tex]No. of moles = \frac{mass}{molar mass}\\= \frac{42.3 g}{18 g/mol}\\= 2.35 mol[/tex]
Hence, molecules of water are calculated as follows.
[tex]2.35 \times 6.022 \times 10^{23} molecules\\= 14.152 molecules[/tex]
Thus, we can conclude that there are 14.152 molecules in 42.3 g sample of water, [tex]H_{2}O[/tex].
