Question

The number of electrons which will together weight one gram is :

• A. $1.098\times {10}^{27}$electrons
• B. $9.1096\times {10}^{31}$ electrons
• C. $1$ electron
• D. $1\times {10}^4$ electrons

Answer 1

The correct option is A $1.098\times {10}^{27}$electrons

Mass of one electron $=9.1096\times {10}^{-31}$ kg

Number of electrons $\times$ mass of 1 electron $=1g={10}^{-3}kg$

$N\times 9.1096\times {10}^{-31}={10}^{-3}$

$N=\frac{{10}^{-3}}{9.1096\times {10}^{-31}}$

$N=1.098\times {10}^{27}$ electrons

Option A is correct