An electron has a charge of
a. –1 and the same mass as a proton
b. +1 and the same mass as a proton
c. –1 and a smaller mass than a proton
d. +1 and a smaller mass than a proton

The correct answer is C. An electron has a charge of -1 and a smaller mass than a proton. Proton has the same mass with the neutron. The ratio between the mass of a proton and an electron is about 2000. An electron has an equal value but negative charge with the proton.

1) according to the law of conservation of mass ,in all chemical reactions total mass is unchanged