How many coulombs of charge do 50 * 10^31 electrons possess

Quantity of Charge, Q = ne

Where n = number of electrons

e = charge on one electron = - 1.6 * 10 ^-19 C.

n = 50 * 10^31 electrons

Q = (50 * 10^31) * (-1.6 * 10 ^-19) = - 8 * 10^13 C.

Note that the minus sign indicates that the charge is a negative charge.