Question

The number of water molecules in a drop of water weighing 0.018 g is ​

Answer 1

Number of moles=0.018/18=0.001 moles of water. 1mole of water[ 18g ] contains 6.022 x 10²³ molecules .

Answer 2

$\large\sf\red{ 6.023 \times 10^{19}}$