پاورپوینت انگلیسی کاتالیزور

Catalysis is the process of increasing the rate of a chemical
reaction by adding a substance known  as
a catalyst , which is not consumed in the catalyzed reaction and can continue
to act repeatedly.Because of this , only very small amounts of catalyst are
required to alter the reaction rate in principle.

In general , chemical reactions occur faster in the presence of a
catalyst provides an alternative reaction pathway whit a lower activation
energy than the non-catalyst mechanism. In catalyzed mechanisms , the catalyst
usually reacts to form a temporary intermediate , which than regenerates the
original catalyst in a cyclic process. A substance which provides a mechanism
with a higher activation energy does not decrease the rate because the reaction
can still occur by the non-catalyzed route. An added substance which does
reduce the reaction rate is not considered a catalyst but a reaction inhibitor.