is oxidation an exothermic or an endothermic reaction ???

 exothermic................ fr example....combustion... :)

 oxidation reactions such as combustion are exothermic reactions.

It depends upon the reaction dear.. It may be exothermic or endothermic.

For example, as everyone's saying, combustion is an exothermic reaction, but there are some reactions which are endothermic.. Sorry, can't come up with an example right now, but when I remember one, I'll let you know.

If it's about some specific reaction, put it up so that we can help you out better.

Hope this helps!

 i agree with snapshots' answer....do remember one thing always, the reactions which happen on their own will always be exothermic, because they are going to a more stable state.

now think of something u have not heard like making oxygen react with say a nobel gas. :D...

obviously it wont happen on its own. nobel gases are super stable.

so u ll need to give it a hell lot of energy to do so , which will make it a endothermic reaction. 

and if u are wondering, yes nobel gases can undergo reactions.

oxidation reaction which includes heat energy to react are endothermic as they are absorbing to bring in a chemical change or to produce the products

Oxidation reaction is that in which addition of oxygen and removal of hydrogen takes place.

Consider the following equations.

You must have observed that in these reactions addition of oxygen and removal of hydrogen are taking place.

As you can see from these reactions that Heat is released in the reaction so it is an exothermic reaction.

oxidation reaction which includes heat energy to react are endothermic as they are absorbing to bring in a chemical change or to produce the products

it is an endo thermic reaction

Oxidation of what, by what? We often refer to something as an oxidation reaction, but it's actually an oxidation/reduction reaction: one species loses electrons, the other gains them.It's very easy to think of exothermic oxidation/reduction reactions, such as combustion of carbon or hydrogen in oxygen, but there are examples of endothermic oxidation/reduction reactions, too. For example, 0.5 I2(s) + 0.5 Cl2(g) = ICl(g) is an oxidation/reduction reaction: iodine oxidizes (loses electrons) and chlorine gains them (is reduced). The enthalpy of this reaction is 17.78 kJ/mol at 298 K. The reaction is spontaneous, though: dG = -5.44 kJ/mol at 298 K.Another endothermic example is the partial oxidation of sulfur by oxygen: S(s) + 0.5 O2(g) = SO; dH = 6.26 kJ/mol, dG = -19.87 kJ/mol. Of course, the next part of the reaction (that makes SO2), is highly exothermic and very favorable, so that proceeds quickly, but the reaction I wrote is an oxidation-reduction reaction that's endothermic.

Sol:The reaction in which a substance gains oxygen or loses hydrogen is called an oxidation reaction.

For example, when copper (Cu) is heated in the presence of air, it gets oxidised to form copper oxide (CuO). The chemical equation involved in this reaction can be represented as

Since heat energy is released in this process, this reaction is exothermic.