Question

The common water molecule is polar because: It contains three polar covalent bonds. It contains one polar covalent bond. It contains no polar bonds, but is symmetrical. It has an asymmetrical shape.

Answer 1

Answer: It has an asymmetrical shape.

Explanation:

`:{\text{Number of electrons}} =(1)/(2)[V+N-C+A]`

where, V = number of valence electrons present in central atom i.e. oxygen = 6

N = number of monovalent hydrogen atoms bonded to central atom=2

C = charge of cation = 0

A = charge of anion = 0

`H_2O`

`{\text{Number of electrons}} =(1)/(2)[6+2-0+0]=4`

The number of electrons is 4 that means the hybridization will be
`sp^3` and the electronic geometry of the molecule will be tetrahedral.

But as there are two atoms around the central carbon, two positions will be occupied by lone pair of electrons. The repulsion between lone and bond pair of electrons is more and hence the molecular geometry will be bent as hence the molecule is asymmetrical and polar due to presence of lone pair of electrons.

Answer 2

We have to choose the correct answer why water molecule is polar.

The correct answer is: It has an asymmetrical shape.

Water molecule has angular shape and two lone pairs of electron. O-atom is central atom ans to it two H-atoms are connected in an angular shape.

O-atom is more electronegative, bond moment acts towards O-atom. As a result, the resultant dipole moment (μR, as shown in figure attached herewith) acts towards lone pairs of electron.

Therefore, water molecule is polar.

Water contains only two polar covalent bonds neither three nor one polar covalent bonds.