Question

calculate the number of atoms of oxygen present in 120 gram of nitric acid

Answer 1

HNO3 is formula of nitric acid ,
in one mole of nitric acid , 3 mole of oxygen atoms present .

no of mole of HNO3 = 120/63 = 1.904
so,
no of mole of O- atoms = 1.904 × 3 = 5.712

so, no of O-atoms = 5.712 × 6.023 × 10²³ = 34.417 × 10²³

= 3.4417 × 10²⁴