Question

Calculate the total number of electrons present in $18mL$ of water.

Answer 1

Volume of water $=18$ $mL$

Since denisty of water = 1 g/mL

$\therefore$ Mass of water $=18$ $grams$

No. of moles of water $=\frac{18}{18}=1$

$1$ molecule of $H_{2}O$ has $10$ electrons

$\therefore 1$ mole $=6.023\times {10}^{23}$ molecules

$\therefore$ No. of electrons $=6.023\times {10}^{23}\times 10=6.023\times {10}^{24}$