Question

What is the oxidation number of $Br$ in $\,BrCl$ ?

Answer 1

Hint : We know that we can solve this question by summing the oxidation number of the compound since in the given compound is neutral and has net charge zero. Assign a random variable ‘x’ for calculating oxidation number of $Br.$ The structure should be considered in these types of questions. This compound has a fractional oxidation state.

Complete Step By Step Answer:
The oxidation number of an element is defined as the charge the atom of an element has in its ion or appears to have when it is in a combined form with other atoms. The oxidation number is also known as the oxidation state. In neutral compounds, the sum state of all the atoms is zero. In complexion, the sum of the oxidation state of all atoms in the ion is equal to the charge on the ion. The oxidation number of an atom or element is a number that indicates the total number of electrons lost or gained by it. The given the definition (to follow), the oxidation state of $Br$ is $+I,$ and $Cl~$ is $-I.$
By definition, oxidation number is the charge left on the given atom when all the bonding pairs (of electrons) are broken, with charge devolving to the most electronegative atom. Since chlorine is more electronegative than bromine, clearly the $2$ bonding electrons devolve to $Cl.$ By this reasoning can you assign oxidation numbers to the interhalogen $I{{F}_{7}}.$

Note :
Remember that there are certain rules for calculating the oxidation number; Oxidation number of any free element is zero. Oxidation number for a monatomic ion is equal to the net charge on it. Hydrogen, in general, has an oxidation state equal to $+1.$ However, it is $-1$ in forms of a compound with an element with lesser electronegativity.