We want to find how much charge is on the electrons in a nickel coin. follow this method. a nickel coin has a mass of about 5 g. find the number of atoms in a nickel coin. each mole (6.02 * 1023 atoms) has a mass of about 58 g. answer in units of atoms.

The mass of a nickel coin is 5 g.

1 mol of Ni weighs 58 g. 1 mol contains 6.022 x 10²³ atoms of Ni.

therefore in 58 g there are 6.022 x 10²³ atoms of Ni

then in 5 g the number of Ni atoms are - 6.022 x 10²³ / 58 x 5 = 5.2 x 10²² Ni atoms

Therefore number of Ni atoms are 5.2 x 10²² atoms in a nickel coin