Question

What is the oxidation number of $\mathrm{Cr}\mathrm{in}{\mathrm{CrO}}_2{\mathrm{Cl}}_2$?

Answer 1

1. The oxidation state or oxidation number is defined as the loss or gain of electrons from an atom, molecule, or compound.
2. The Chromyl chloride is a neutral atom as it does not have any charge on it.

Given oxidation number

• The oxidation number of Oxygen is -2.
• The oxidation number of Chlorine is -1.

Calculating the oxidation number of Chromium.

• Let the oxidation number of Chromium be “x”.
• Equating all the atoms equivalent to 0.
• $(\mathrm{No}.\mathrm{of}\mathrm{Chromium}\mathrm{atom})\times \left(\mathrm{x}\right)+(\mathrm{No}.\mathrm{of}\mathrm{Oxygen}\mathrm{atom})\times (\mathrm{Oxidation}\mathrm{No}.\mathrm{of}\mathrm{Oxygen})+(\mathrm{No}.\mathrm{of}\mathrm{Chlorine}\mathrm{atom})\times (\mathrm{Oxidation}\mathrm{number}\mathrm{of}\mathrm{Chlorine})=0$
• $1\left(\mathrm{x}\right)+2\left(-2\right)+2\left(-1\right)=0$
• $\mathrm{x}=+6$
• Thus, Chromium is having +6 Oxidation state in Chromyl chloride.