Question

one exampla of redox reaction???..

Answer 1

A good example is the reaction between hydrogen and fluorine in which hydrogen is being oxidized and fluorine is being reduced:

H
2 + F
2 → 2 HF

We can write this overall reaction as two half-reactions:

the oxidation reaction:

H
2 → 2 H+ + 2 e−

and the reduction reaction:

F
2 + 2 e− → 2 F−

Analyzing each half-reaction in isolation can often make the overall chemical process clearer. Because there is no net change in charge during a redox reaction, the number of electrons in excess in the oxidation reaction must equal the number consumed by the reduction reaction (as shown above).

Elements, even in molecular form, always have an oxidation state of zero. In the first half-reaction, hydrogen is oxidized from an oxidation state of zero to an oxidation state of +1. In the second half-reaction, fluorine is reduced from an oxidation state of zero to an oxidation state of −1.

When adding the reactions together the electrons are canceled:

H
2→2 H+ + 2 e−F
2 + 2 e−→2 F−H2 + F2→2 H+ + 2 F−

And the ions combine to form hydrogen fluoride:

2 H+ + 2 F− → 2 HF

The overall reaction is:

H
2 + F
2 → 2 HF

Answer 2

1.H2 + F2 = 2HF

2.Fe + CuSO4 + → FeSO4 + Cu (Fe oxidized, Cu reduced)

3.C6H12O6+ 6 O2 → 6 CO2 + 6 H2O

4.2 KmnO4 + 3 Na2SO3 + H2O → 2 MnO2 + 3 Na2SO4 + 2 KOH

5.3 CuS + 8 HNO3 → 3 CuSO4 + 8 NO (g) + 4 H2O

Hope it helps....