what is the product formed from CH3CH2CH(OH)CH3----->reacting with H2SO4 and heat?

Answer 1

The product will be 2-Butene, NOT 1-Butene.

After the -OH becomes protonated and leaves, you are left with a secondary carbocation. Now two different protons can be picked off, each producing a different product. You will get 2-Butene because it is more stable than 1-Butene (2-Butene is more stable because the double bond is more substituted).

Answer 2

But-1-ene.

Some but-2-ene might also be formed as a side-reaction.