How many moles of electrons weigh one kilogram?

Options

A. `6.023 xx 10^23`
B. `(1)/(9.08) xx 10^31`
C. `(6.023)/(9.108) xx 10^54 `
D. `(1)/(9.108 xx 6.023) xx 10^8`

Answer

D

Explanation

Mass of 1 mol of electrons `= 9.1 xx 10^(-31) xx 6.023 xx 10^23`
`= 9.1xx 6.023 x 10^(-8) kg`
Number of moles present in 1 kg ` = (1)/(9.1 xx 6.023) xx 10^8 kg `