Question

why a charge of 3.3×10-19C is not possible?​

Answer 1

As per quantization of charge: Electric charge can exist only as an integral multiple of charge on an electron (-e) i.e. q = ± ne, where n is an integer. The Possible values of electric charge are q = ± 1e; ± 2e; ± 3e... Charge less than the charge on an electron (i.e. e = 1.6 * 10-19 C) is not possible.