Question

Find out the valency and covalency shown by the: (a) Hydrogen atom

Answer 1

Valency:

The combining capacity of the atom of an element with the atoms of other elements in order to acquire eight electrons in its outermost shell is known as valency.

Valency of Hydrogen atom $\mathbf{\left(}\mathbf{H}\mathbf{\right)}$:

1. Hydrogen atom $\mathbf{\left(}\mathbf{H}\mathbf{\right)}$ has atomic number $1$. Thus, the number of electrons in a Hydrogen atom are $1$.
2. The electronic configuration of Hydrogen is $\left(1\right)$.
3. In order to acquire two electrons in the outermost shell, Hydrogen atom gains 1 electron in the outermost shell.
4. Thus, the valency of Hydrogen is $1$.

Covalency:

The number of electrons shared by an atom with another atom during the formation of covalent molecule to have eight electrons in its outermost shell is known as covalency.

Covalency in Hydrogen atom $\mathbf{\left(}\mathbf{H}\mathbf{\right)}$:

1. Hydrogen atom $\mathbf{\left(}\mathbf{H}\mathbf{\right)}$ has atomic number $1$. Thus, the number of electrons in a Hydrogen atom are $1$.
2. The electronic configuration of Hydrogen is $\left(1\right)$.
3. In order to form Hydrogen molecule $\left(H_2\right)$, two Hydrogen atoms share one electron each and attain stable nearest noble gas configuration.
4. As one Hydrogen atom shares one electron, the covalency of Hydrogen is $1$.