How many moles of electrons weigh one kilogram?

Options

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

Answer

D

Explanation

Number of `e^(-)` weighing 1kg `= (1)/(9.108 xx 10^(-31) kg) = (1)/(9.108) xx 10^(31)`
Number of moles of `e^(-) = (1)/(9.108 xx 6.023) xx (10^(31))/(10^(23)) = (1)/(9.108 xx 6.023) xx 10^(8)`