Question

The volume of a drop of water is 0.05 ml and the density of water is 1.0 g/ml. How many water molecules are present in a drop of water?
(1) 1.7 × 10²¹
(2) 5.4 x 10²³
(3) 22 x 10²⁶
(4) 1.7 x 10²⁰​

Answer 1

Explanation:

So, we can count moles of water in a given amount. Count the number of particles from the number of moles obtained above by the Avogadro's constant. From the above statements we can conclude that the number of water molecules present in a drop of volume 0.05 mL water is 1.67 x 1021.