Calculate the approximate number of molecules in a drop of water with a mass of 0.10 g.

A.

3 * 1021 molecules

B.

2 * 1023 molecules

C.

6 * 1021 molecules

D.

4 * 1023 molecules

Option A. 3 * 10^21 molecules

Explanation:

From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. This means that 1mole of H20 also contains 6.02x10^23 molecules.

1mole of H2O = (2x1) + 16 = 2 + 16 = 18g

If 1mole (i. e 18g) of H2O contains 6.02x10^23 molecules,

Therefore 0.1g of H2O will contain = (0.1 x 6.02x10^23) / 18 = 3 x 10^21 molecules

your answer is D - _ - bc they want the approximate