Question

How many water molecules are there in 36 g of water? express your answer as a multiple of avogadro's number na. (the molecular structure of a water molecule is h2o.)'?

Answer 1

M H2O = 18 g/mol

In 18 g of water we have 6,02 × 10^23 molecules.

18 g ----- 6,02 × 10^23
36 g ----- x

x = 36 g × 6,02 × 10^23 / 18 g = 12,04 × 10^23 = 1,204 × 10^24

Answer is 1,204 × 10^24

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