[firedamage]

1)Bleaching a stain
2)Burning of a match
3)Rusting of an iron nail

is it the answer should be 1)single displcaement reaction 2)combustion reaction 3)decompositon reaction?

[Arkcon]

Well, you might have to guess, but can you break these words down into chemical reactions?  Reactants and products aren't given to you, but maybe you can take a guess.

[Astrokel]

They are asking for evidence and not type of reaction. Follow Arkcon's post and you will know why.

[firedamage]

i am still not understand what the question say..

[Borek]

This is related to the other question - what is a difference between chemical and physical change?

[firedamage]

then what is the chemical equation for the bleaching of a stain?Do stain has chemical formula..and what is the formula for matches??i only know 3)2Fe+2O2=2FeO2

[Arkcon]

then what is the chemical equation for the bleaching of a stain?Do stain has chemical formula..

See, now that's a hard one to be sure.  they should have given you more info.  Could this have been an example from your textbook?  Did they describe how bleach works?  Could you just assume they mean household bleach?  Or maybe the natural bleaching power of sunlight?  What are the similarities?  How would you name the reaction?  You'll have to pick a reaction-type other than the examples you've posted here, but you have mentioned this type of reaction in your other questions.

and what is the formula for matches??

Can you take a guess as to which of your suggested types the match reaction applies.

[Astrokel]

what is the formula for matches??

well, let's say you burn a match and before you start burning, you need a source of energy to lit it up. That could be friction when you rub the matchstick against the box. Once it started to lit up, you still need a source of energy for it to continue burning, and that is where you need to think. What or where is this source of energy that let it continue burning? This is essentially the evidence of chemical change.

http://www.chemicalforums.com/index.php?topic=27229.msg102721#msg102721

[firedamage]

the textbook just do not give enough information for someone newbie like me.
I just couldn't find the solution...!!

[Arkcon]

For your benefit, and the benefit of new chemistry students who browse this posting, can you list the reaction types your book mentions, and an example of each?  This exercise may give you the "a-ha" moment you need, and will be helpful in later questions you may have.  Also, it will put us all on the same page.  For example, in my day, we were taught single-displacement reactions, and double-displacement reactions, while you call the latter ones -- metathesis reactions.  Try to pull all your posts together.