Question

chem ll

For the reaction KCIO, — KCI + O2 assign oxidation numbers to each element on each side of the equation. K in KCIO: K in KCI:

Answer 1

1 & 2) Oxidation state of K in KClO2 is +1 and Cl is +3 and Oxygen is -4

Reason: Chlorite oxidation state is -1 (ClO2)-

where as Cl oxidation state is +3 ( as oxygen is having -2, we have 2 oxygen hence -4 and potassium as +1 hence Cl oxidation state is +3.

1 & 2) Oxidatino of K in KCl and Cl is KCl

Oxidation state of K is +1 and Cl is -1

2) Oxidation state of O in O2 is zero (O2 is Diatomic which have same electronegativity. Electrons share between double bond and the electron lie in center of the molecule. Both of them attract these electrons with the same force. Because of this force there is no shifting of electrons and the charge is zero)

2) which is oxidized and which is reduced

Reason: potassium is oxidized and Cl is reduced. (removal of electrons is oxidtion and addition of electrons is reduction)

Hydrogen fuel cell eqn:

in the below eqn. Hydrogn is getting oxidized ( zero to +1) and oxygen is getting reduced (zero to -2)

Oxygen is reducing 2H2 + O2 — 2H20 Hydrogen is oxidizing

Balance eqn Answer:

6Cr2+ + H2MoO4 + 6H+ = 6Cr3+ + Mo + 4H2O

In order to balance equation you would require extra hydrogens in reactant side and water is the by-product.