Question

Calculate the total number of electrons present in 1.4 g of dinitrogen gas.

Answer 1

Mass of nitrogen = 1.4

Molar mass of nitrogen = 28 g/mol

Amount of nitrogen = {1.4 g}/{28 g/mol} = 0.05 mol

No. of nitrogen molecules in 0.05 mol

= 6.023 x 10²⁵ mol^-1 x 0.05 mol

= 3.0115 x 10²²

Number of electrons in one molecules of nitrogen

(N₂) = 14

Therefore, total number of electrons in 14 g of nitrogen

= 3.0115 x 10²² x 14

= 4.2154 x 10²³