Assuming composition of universe to be 90% hydrogen and 10% helium, by mass. It represent that :

Engineering

Chemistry

Mole and Its Calculation

Question

There are 18 hydrogen atoms in the universe per atom of helium.

There are 36 hydrogen atoms in the universe per atom of helium.

The average molecular mass of universe is $\frac{40}{19}$ .

There are 9 hydrogen atoms in the universe per atom of helium.

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Moles of H₂ = $\frac{90}{2}$ = 45
Moles of He = $\frac{90}{4}$ = 2.5
$\frac{Moles of H - atom}{Moles of He - atom} = \frac{45 \times 2}{2 .5}$ = 36

Percent Average (By mass ) = $\frac{100}{\frac{90}{2} + \frac{10}{4}} = \frac{40}{19}$