Question

What is the oxidation state of chlorine in $NaCl{{O}_{2}}$?

Answer 1

This is a neutral compound or there is no overall charge on the compound so, the sum of the oxidation states of all the atoms will be equal to 0. Take the value of the oxidation state for alkali metal atoms as +1 and the oxidation state for the element belonging to group 16 as -2.

Complete answer:
Oxidation state is the charge on the element when it is present with other elements in a compound and it is also known as oxidation number, it can be positive, negative, zero, and even fractional.
To calculate the oxidation state of an atom in the element, we must find all the oxidation states of the other atom, and if the compound is neutral then the sum of the oxidation states of all the atoms will be equal to 0. If there is an overall charge on the compound then it will be equal to the charge not to 0.
The given compound in the question is $NaCl{{O}_{2}}$, as we can see that there is no overall charge on the compound, so it is a neutral compound. Sodium is the element of alkali metals, so its oxidation number will be +1 and oxygen is the element of group 16, so its oxidation state will be -2. Now, putting all the values, we get:
$+1+x+2(-2)=0$
$+1+x-4=0$
$x-3=0$
$x=+3$
So, the oxidation state of chlorine in $NaCl{{O}_{2}}$ is +3.

Note:
Due to the +3 oxidation state of chlorine in $NaCl{{O}_{2}}$, its proper name is sodium chlorate (III). The oxidation state of oxygen in all the compounds is -2, except the oxidation state of oxygen in peroxides is -1.