An electron is a fundamental subatomic particle which carries one unit negative charge and has a mass nearly equal to `1//186` the mass of an_______atom.

Options

A. `He`
B. `H`
C. `Be`
D. `Li`

Answer

B

Explanation

The value of `e//m` for an electron was found to be almost `1836` times larger than for an `H^(+)` ion. The magnitude of the charge is the same for the `H^(+)` ion and for the electron. Therefore, the mass of the electron is `1836` times smaller than that of `H` atom.