80 g of oxygen contains as many atoms as in

Options

A. 10 g of hydrogen
B. 5 g of hydrogen
C. 80 g of hydrogen
D. 1 g of hydrogen

Answer

B

Explanation

No. of mole of oxygen ` = (80)/(16) = 5` mol
1 mol contains avogadro no. of atom i.e., `6.02 xx 10^(23)` atoms.
`therefore ` 5 mol contains `6.02 xx 10^(23) xx 5` atoms
` = 30.1 xx 10^(23)` atoms
Similarly in option (b)
No. of mol of hydrogen `= (5)/(1) = 5 ` mol
5 mol of hydrogen contains `= (5)/(1) = 5` mol.