Question

The order of reactivity of some interhalogens is as follows:
\({\rm{Cl}}{{\rm{F}}_{\rm{3}}} > {\rm{Br}}{{\rm{F}}_{\rm{3}}} > {\rm{I}}{{\rm{F}}_{\rm{7}}} > {\rm{Br}}{{\rm{F}}_{\rm{5}}} > {\rm{BrF}}\)

Answer 1

Hint: Halogens react with each other to form a number of compounds termed as interhalogen compounds. The general formula is ${A{X_n}}$ where X will be more electronegative than A and n is the number of X halogen which can be 1, 3, 5 or 7. In ${A{X_n}}$, A is less electronegative and larger in size and X is more electronegative and smaller in size

Complete step by step answer:
Firstly, we will learn about the concept of interhalogen compounds in which the covalent bonding with two different halogens forms the interhalogen compounds. . Interhalogen compounds are diamagnetic in nature and are colorless. The thermal stability of these compounds increases with increase in electronegativity difference.
Interhalogen compounds are more reactive than the diatomic molecule since A-X bond is weaker than the A-A bond or X-X bond except ${F_2}$.
If we move left to right in a period of periodic table, the size of the atom decreases. The diatomic molecule ${F_2}$ is not stable because fluorine has very small size due to which interelectronic repulsion is very high making ${F_2}$ molecule unstable.
Reactions of interhalogen compounds are similar to that of the halogens. Interhalogen compounds on hydrolysis give oxy-acid and halogen acids.
There is no particular reason behind the reactivity order of the interhalogen compounds. The given order has been established by experimental data.

Note:
We need to remember one important thing about the stability of interhalogen compounds is that interhalogen compounds with higher electropositive character will have more stability. The electropositivity of the halogen compounds increases on moving down the group i.e. \[{\rm{I}} > {\rm{Br}} > {\rm{Cl}}\;{\rm{ > }}\;{\rm{F}}\].