Some Basic Concepts of Chemistry - Result Question 13 — JEE PYQ Chapterwise

Answer:

Correct Answer: 23. (d)

Solution:

$\begin{aligned} & \text { 23. Mass of an electron }=9.108 \times 10^{-31} \mathrm{~kg} \\ & \because \quad 9.108 \times 10^{-31} \mathrm{~kg}=1.0 \text { electron } \\ & \begin{aligned} \therefore \quad 1 \mathrm{~kg} & =\frac{1}{9.108 \times 10^{-31}} \text { electrons }=\frac{10^{31}}{9.108} \times \frac{1}{6.023 \times 10^{23}} \\ \quad= & \frac{1}{9.108 \times 6.023} \times 10^8 \text { mole of electrons }\end{aligned}\end{aligned}$