Question

Water molecules have hydrogen and oxygen in the ratio 1:8 by mass. Find the ratio of number of atom of elements in the molecule

Answer 1

Ratio of number of moles 1 /1 ∶ 8/ 16

Number of moles
= Mass / Atomic mass

Number of moles of hydrogen = 1/ 1 = 1

Number of moles of oxygen
= 8 /16 = 1/ 2

Since ratio of number of moles 2:1

Therefore ratio of number of molecules will also be 2:1

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