Question

What is the oxidation number of the halogen atom in the following
\[C{l_2}O\]

Answer 1

Hint: The elements which are occupying the group VIIA (17) of the periodic table are known as halogens. According to the modern periodic table fluorine, chlorine, bromine, iodine, and astatine are said to be halogens. They are reactive non-metallic elements that form strongly acidic compounds with hydrogen from which simple salts can be made.

Complete answer:
Like every other group of the modern periodic table, the elements of group 17 which are known as halogens also show similarities in physical and chemical properties.
\[C{l_2}O\] is the molecular formula used to represent Dichlorine Monoxide. When it is at room temperature it exists as a brownish-yellow gas that is soluble in both water and organic solvents.
Dichlorine monoxide is made up of two different types of atoms, Chlorine, and Oxygen. The net charge on the molecule is zero ( $0$ ).Hence the sum of the oxidation number of individual atoms will be zero. Since oxygen is a highly electronegative element its oxidation number is $ - 2$ .Let the oxidation number of the chlorine atom be $x$ .
Taking the sum of oxidation number of individual elements,
$2x + ( - 2) = 0$
Taking the constant on L.H.S,
$x = \dfrac{2}{2}$
Therefore by solving the equation we get,
$x = 1$
Hence the oxidation number of halogen(Chlorine) in the molecule is $ + 1$.

Note:
Dicholrine monoxide has various industrial applications. It is used as an intermediate in the manufacture of calcium hypochlorite and in industrial sterilization. Chemically, it is a member of the chlorine oxide family of compounds, as well as being the anhydride of hypochlorous acid. It acts like a strong oxidizer and chlorinating agent.