Q. 6.101 - An Introduction to General, Organic, and Biological Chemistry

Question

State the number of valence electrons, bonding pairs, and lone pairs in each of the following Lewis structures:

Step-by-Step Solution

Answer

a. $2$ valence electrons, $1$ bonding pairs, and $0$ lone pairs of electron.

b. $8$ valence electrons, $1$ bonding pairs, and $3$ lone pairs of electron.

c. $14$ valence electrons, $1$ bonding pairs, and $6$ lone pairs of electron.

Part(a) Step 1: Given information

We have been given the Lewis structure of ${\mathrm{H}}_2$ molecule.

We need to find the number of valence electrons, bonding pairs, and lone pairs 

Part(a) Step 2: Explanation

Each Hydrogen atom has one valence electron so the given Lewis structure of ${\mathrm{H}}_2$ molecule have $2$ valence electrons. It has $1$ bonding pair and $0$ lone pairs of electron.

Part(b) Step 1: Given information

We have been given the Lewis structure of $\mathrm{HBr}$ molecule.

We need to find the number of valence electrons, bonding pairs, and lone pairs 

Part(b) Step 2: Explanation

Hydrogen has $1$ valence electron and Bromine have $7$ valence electrons so the given Lewis structure of  $\mathrm{HBr}$ molecule have $8$ valence electrons. It has $1$ bonding pair and $3$ lone pairs of electron over Bromine atom.

Part(c) Step 1: Given information

We have been given the Lewis structure of ${\mathrm{Br}}_2$ molecule.

We need to find the number of valence electrons, bonding pairs, and lone pairs 

Part(c) Step 2: Explanation

Each Bromine atom have $7$ valence electrons so the given Lewis structure of ${\mathrm{Br}}_2$ molecule have $14$ valence electrons. It has $1$ bonding pair and $6$ lone pairs of electron, $3$ lone pair on each Bromine atom.