Electrical Charge is a property of matter that causes it to experience a force when place in an electromagnetic field. Charge is measured in coulombs.
The change in the charge is 2.2- (2.0)= 4.2 μ c.
1 electron has a charge of 1.6 ×10∧-19 coulombs
Therefore, the number of electrons will be;
= (4.2 ×10∧-6)/ (1.6 ×10∧-19)
= 2.625 × 10∧13 electrons