To determine the number of electrons that make up 1 Coulomb of negative charge, we can use the elementary charge (e), which represents the magnitude of the charge of a single electron. The elementary charge has a value of approximately 1.602 x 10^-19 Coulombs (C).

To find the number of electrons that correspond to 1 Coulomb, we can divide the charge of 1 Coulomb by the elementary charge of a single electron:

Number of electrons = (1 Coulomb) / (1.602 x 10^-19 C/electron)

Calculating the division, we get:

Number of electrons ≈ 6.24 x 10^18 electrons

Therefore, approximately 6.24 x 10^18 electrons make up 1 Coulomb of negative charge.