Question

How many moles of electron weigh 1 Kg?

• A. $6.023\times {10}^{23}$
• B. $\frac{1}{9.108}\times {10}^{31}$
• C. $\frac{6.023}{9.108}\times {10}^{54}$
• D. $\frac{1}{9.108\times 6.023}\times {10}^8$

Answer 1

The correct option is D $\frac{1}{9.108\times 6.023}\times {10}^8$

Mass of an electron = $9.108\times {10}^{-31}$g

$\because 9.108\times {10}^{-31}kg=1.0$ Electron

$1kg=\frac{1}{9.108\times {10}^{-31}}$ Electrons

$6.023\times {10}^{23}$ electrons make 1 mole, then

$\frac{1}{9.108\times {10}^{-31}}$ Electrons will be = $\frac{1}{9.108\times {10}^{-31}}\times \frac{1}{6.023\times {10}^{23}}$

= $\frac{1}{9.108\times 6.023}\times {10}^8$ moles of Electrons