How many moles of electrons weigh one kilogram?

Options

A. (a)`6.023xx10^(23)`
B. (b)`1/9.108xx10^(23)`
C. (c )`6.023/9.108xx10^(54)`
D. (d)`1/(9.108xx6.023)xx10^(8)`

Answer

D

Explanation

Mass of an electron `=9.108xx10^(-31) kg`
Thus, `:' 9.108xx10^(-31) kg` of electron contain
`=1/(6.023xx10^(23))` moles
`:. 1 kg` of electrons will contain
`=1/(6.023xx10^(23))xx9.108xx10^(-31)` moles
`=1/(6.23xx9.108)xx10^(8)` moles