We know that the charge on an electron is negative and it is 1.6⨯10^-19 coulomb.

We need to calculate the number of electrons constituting one coulomb of charge.

e = 1.6 × 10^-19 C

Total charge required for 1Coulomb.

∴  q = 1C……….(1)

The formula to calculate the charge is

q = ne

where

q = charge

e = number of electrons

n = q/e……….(2)

Substituting equation (1) in equation (2) we get

n = 1/(1.6 × 10^-19)

n = 6.25 × 10^18 electrons ≅ 6 × 10^18 electrons

So 1 Coulomb of charge contains 6 × 10^18 electrons.