Identify the oxidising agent (oxidant) in the following reactions

(a) Pb3O4 + 8HCl 3PbCl2 + Cl2 + 4H2O


(b) Mg + 2H2O Mg (OH)2 + H2


(c) CuSO4 + Zn Cu + ZnSO4


(d) V2O5 + 5Ca 2V + 5CaO


(a) Pb3O4 is the oxidizing agent because it is reduced itself and oxidises HCl to Cl2. In HCl, H has oxidation state of +1 and Cl has oxidation state of -1. In Cl2, Cl has oxidation state of 0. An increase in oxidation state is oxidation.


(b) H2O is the oxidizing agent because it reduces itself and oxidises Mg to Mg(OH)2. Oxidation state of Magnesium in Mg is 0. In Mg(OH)2, Mg has an oxidation state of +2. An increase in oxidation state is oxidation


(c) CuSO4 is the oxidizing agent as it reduces itself and oxidises Zn to ZnSO4.


In Zn, Zinc has an oxidation state of 0. In ZnSO4, Zinc has an oxidation state of +2. An increase in oxidation state is oxidation.


(d) V2O5 is the oxidizing agent as it reduces itself and oxidises Ca to CaO.


In Ca, Calcium has an oxidation state of 0. In CaO, Calcium has an oxidation state of +2. An increase in oxidation state is oxidation


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