What is reduction reaction ?
Reduction: The addition of hydrogen to a substance or removal of oxygen from a substance is called reduction.
Oxidation and reduction occur together in a reaction.
Zinc reacts with steam to produce zinc oxide and hydrogen gas.
Zn(s) + H2O(g) -----> ZnO(s) + H2(g)
In above reaction, Zinc(Zn) is getting oxidized as addition of oxygen to zinc is taking place and water is getting reduced as removal of oxygen from water is taking place.
ii Aluminum reacts with steam to form aluminum oxide and hydrogen gas.
2Al(s) + 3H2O(g) -----> Al2O3(s) + 3H2(g)
In above reaction, Aluminium(Al) is getting oxidized as addition of oxygen to aluminum is
taking place and water is getting reduced as removal of oxygen from water is taking place.