Which Lewis electron-dot diagram represents a molecule having a nonpolar covalent bond?

1. Compound that contains both ionic and covalent bond is

2. Electronegativity difference is high in water.

Explanation:

Covalent bond is the bond in which sharing of electrons takes place between two atoms combining. These compounds do not dissociate into its ions when mixed in water.

Ionic bond is the bond when there is complete sharing of electrons taken place between the two atoms combining. These compounds dissociate into its respective ions when mixed in water.

For the given chemical reaction:

are ionic compounds and is a covalent compound.

In , ionic bond is present between sodium and bicarbonate ions. But covalent bond is present between the atoms of bicarbonate ions. Covalent bonds are present between C=O, C-O-H, and C-O(-) atoms.

The difference in electronegativity of the elements forming a compound can easily tell us about the polarity of the compound.

More the electronegativity difference, more polar will be the molecule and vice-versa.

Electronegativity of elements:

Hydrogen: 2.2

Oxygen: 3.44

Nitrogen: 3.04

Electronegativity difference of hydrogen and oxygen = (3.44 - 2.2) = 1.24

Electronegativity difference of hydrogen and nitrogen = (3.04 - 2.2) = 0.84

As, we can see that electronegativity difference of oxygen and hydrogen is more, hence the bond between them will be more polar. Hence, water is more polar than nitrogen.

Lewis dot structures are the structures which shows the number of valence electrons around an element. For a compound, it shows the number of bonded and non-bonded electrons around each element.

The reactant which contain nitrogen in it is and the lewis dot structure of it is shown in the image attached.