Question

The mass of a mole of proton and electron is

• A. $ 6.023\times 10^{23}g $
• B. $1.008 \,g$ and $0.55 \,mg$
• C. $ 9.1\times 10^{-28}kg $
• D. $2 \,g$

Answer 1

Answer: (B)

Mass of a proton $=1.673 \times 10^{-24} g$
$\therefore $ Mass of one mole of proton
$=1.673 \times 10^{-24} \times 6.02 \times 10^{23}$
$=10.07 \times 10^{-1} $
$=1.008 \,g$
Mass of an electron $=9.1 \times 10^{-28} g$
$\therefore $ Mass of one mole of electron
$=9.1 \times 10^{-28} \times 6.02 \times 10^{23}$
$=54.78 \times 10^{-5} g =0.55 \,mg$