(i) Calculate the number of electrons which will together weigh one gram.

(ii) Calculate the mass and charge of one mole of electrons.

(i) As we know that

Mass of one electron = 9.1× 10^-28g

1 electron weighs 9.1× 10^-28g

So, X electrons will weigh 1g

X = [1] / [9.1× 10^-28]

= 1.098×10²⁸ electrons

Therefore 1.098×10²⁸ electrons together weigh 1g.

(ii) By Avogadro’s Law we know that

1 mole of electron = 6.023×10²³ electrons

Mass of one electron = 9.1× 10^-28g

Therefore, Mass of 1 mole of electrons = [6.023×10²³] × [9.1× 10^-28]

= 5.4809× 10^-4g

We also know that charge of one electron = 1.6× 10^-19 C

Therefore, Charge of 1 mole of electron is = [6.023×10²³] × [1.6× 10^-19]

= 96.368×10³ C

Therefore, mass of one mole of electron is 5.481× 10^-4g and the charge is 96.37×10³ C.