Question

Calculate the mass of: (a)one atom of oxygen (b)one molecule of oxygen (c)one ion of oxygen

Answer 1

Dear student

a)

The mass of 1 atom = Gram atomic mass of atom/ 6.022 × 10²³

So, the mass of 1 atom of oxygen = Gram atomic mass of oxygen atom/ 6.022 × 10²³

= 16g/ 6.022 × 10²³

= 2.66 × 10^-23 g

b)

The molar mass of oxygen molecule (O₂) is 32g. This means that there are 6.023 X 10²³ molecules of oxygen in 32g of oxygen. So

mass of 6.023 X 10²³ molecules of oxygen = 32g

mass of one molecule of oxygen = 32 / (6.023 X 10²³) = 5.313 X 10^-23 g

c)
6.023 x 10²³ ions of Oxygen =16g
so, mass of one ion = 16/6.023 x 10^23
= 2.66 × 10^-23 g

​​​​​​
Regards