Question

What do you understand by a lone pair of electrons?
Draw the electron dot diagram of Hydronium ion. $(H=1;O=8)$.

Answer 1

A lone pair refers to a pair of valence electrons that are not shared with another atom and also called non-bonding electron pair. They are found in the outermost electron shell of atoms and can be identified by using a Lewis.

structure.

Hydronium ion is $H_3{O}^{+}$ where valence electron in $H$ is 1 and in $O$ is 6 ($1s^{2}2s^{2}2p^4$). Total valence electrons are 3+6-1=8.