Question

If "catalysts don't take part in chemical reactions and only change the rate of reaction " , the why during catalytic oxidation of alkanes, we get different products using Cu, MoO and when no catalyst is used?

Answer 1

Catalyst can be defined as a substance that donot take part in chemical reaction, only for physical chemistry aspects.

Well, we have organic chemistry, with organic compounds , and physical chemistry , with ionic compounds.

In organic chemistry, catalyst is definined as something that remains unchanged during a chemical reaction. , and not something that doesn't react at all.

Organic and physical chemistry are different , and this is one of the reason why catalyst bahaves differently in organic reactions.

In organic reactions, reaction doesnot occur in single step, but occurs in multiple steps. If you consider any single step, you may find catalyst taking part in a reaction. But, considering sum total of all steps, you will not find catalyst anymore.

So, in orgaic reactions, catalysts do take part in intermediate steps, but not in overall reaction.

Also, each catalyst has a specific heat related to reaction conditions. This related heat, can divert reaction to a specific direction. So, different catalyst can give different products