Question

The bond angle in $\text{O}{{\text{F}}_{2}}$out of $\text{O}{{\text{F}}_{\text{2}}}\text{, C}{{\text{l}}_{\text{2}}}\text{O, B}{{\text{r}}_{\text{2}}}\text{O}$ is minimum. It is because in case of $\text{O}{{\text{F}}_{2}}$:
(A) Electrons are nearer to fluorine due to high electronegativity of F compared to Cl to Br
(B) Lone pair-lone pair repulsion decreases bond angle
(C) Both (a) and (b) is correct
(D) None of the above is correct

Answer 1

Hint: Lets us see what are the factors that affects the bond angle:
- Hybridization: Bond angle depends on the state of hybridization of the central atom
- Lone pair repulsion: Bond angle is affected by the presence of lone pair of electrons at the central atom.
- Electronegativity: If the electronegativity of the central atom decreases, bond angle decreases.With the help of these hints let's see the complete solution.

Complete step by step answer:

Generally the bond angle of any compound depends on the hybridization of the central atom. For example $\text{C}{{\text{H}}_{\text{4}}}$has hybridization of $\text{s}{{\text{p}}^{\text{3}}}$with bond angle of 109.5 degree,$\text{BC}{{\text{l}}_{\text{3}}}$has hybridization of $\text{s}{{\text{p}}^{\text{2}}}$with bond angle of 120 degree.
A lone pair of electrons at the central atom always tries to repel the shared pair of electrons, and it results in decreasing the bond angle.
Sometimes electro negativity also comes into picture which plays a major role in determining the bond angle of any compound. If the electronegativity of the central atom decreases, the bond angle also decreases.
In case of $\text{O}{{\text{F}}_{\text{2}}}$ the bond angle is minimum because the electrons are nearer to fluorine due to high electronegativity of F as compared to other halogens, and because of this repulsion between the electrons decreases the bond angle.
So, we can say that option C is the correct answer.

Note: Always remember these two points:
- Triple bonds repel other bonding-electrons more strongly than double bonds.
- Double bonds repel other bonding-electrons more strongly than single bonds.