[curso]

hey
I really do not know if h2so4 help to form water in product as in
preparation of ethene .. or remove water from product as
ester to prevent reversible reaction .. or as acid to help water to break bond

c2h5oh >>>H2so4+180c>>> c2h4 + H2o


c2h4 + H2o >> h2so4 +110c >> ch3cho


benzen + HNo3 >>h2so4>> nitro benzene + H2O


ch3cooh + c2h5oh >>h2so4>> ch3cooc2h5 + H2O

[TheUnassuming]

It can often be hard to see what is going on simply by looking at the equations of a reaction.  Try drawing out the structure and figuring out the mechanism, it makes it much easier to see the roll of sulfuric acid.

[Babcock_Hall]

I would think about catalysis and leaving group ability.

[Borek]

c2h4 + H2o >> h2so4 +110c >> ch3cho

Please pay attention to the way you format your posts and - especially - formulas.