CBSE Class 10 Answered

• Oxidation is the loss of electrons and reduction is the gain of electrons.
• To explain the involvement of oxidation and reduction in the formation of molecular compounds, the concept of oxidation number was introduced.

Example: Hydrogen combining with oxygen to form water.

• In the formation of water, electron transfer is realised when hydrogen combines with oxygen.
• The hydrogen atom (H) goes from a neutral state, i.e. a zero state (H₂) to a positive state in H₂O, whereas the oxygen atom (O) goes from a neutral state, i.e. a zero state (O₂) to a dinegative state in H₂O.
• It is assumed that there is an electron transfer from H to O, and consequently, H₂ is oxidised and O₂ is reduced.
• The transfer of the charge is partial and considered an electron shift rather than a complete loss of electrons by hydrogen (H) and gain of electrons by oxygen (O).

Example: