Question

The atomic number of an element X is 19. The number of electrons in its ion X⁺ will be ______.

Options

• 18

• 19

• 20

• 21

Answer 1

The atomic number of an element X is 19. The number of electrons in its ion X⁺ will be 18.

Explanation:

An atomic number of 19 means the neutral atom has 19 electrons. The single positive charge on the (X⁺) ion indicates that the atom has lost one electron. Subtracting this lost electron from the original 19 leaves the ion with a total of 18 electrons.