Question

Which of the following statements are wrong ?reduction involves gain of electrons
the oxidation no of reducing agent decreases.
oxidising agent helps to increase the oxidation no. of reducing agent.
oxidation involves loss of electrons​

Answer 1

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Oxidation involves an increase in oxidation number while reduction involves a decrease in oxidation number.

Usually the change in oxidation number is associated with a gain or loss of electrons.

So, whenever a particular species gains electron, another species loses electron which means oxidation and reduction takes place simultaneously.