catalysts

[jasonn93]

Do catalysts actually break the bonds in reactants or just weaken them so that there is a higher chance of successful collision? Thanks =]

[JinXi]

It lowers the activation energy required for reaction to occur, thus increasing the likelihood of successful collisions (which has sufficient energy to break the bonds.)

[toshibaj]

Yeah you don't really need to go into detail. Different catalysts do different things. Just remember the definition above and you'll be fine.

[samiira]

it says in this site http://www.chemguide.co.uk/physical/basicrates/catalyst.html

a catalyst does not "lower the activation energy of the reaction".

if you are asked about this in an exam. The correct form of words is

"A catalyst provides an alternative route for the reaction with a lower activation energy."

[JinXi]

it says in this site http://www.chemguide.co.uk/physical/basicrates/catalyst.html

a catalyst does not "lower the activation energy of the reaction".

if you are asked about this in an exam. The correct form of words is

"A catalyst provides an alternative route for the reaction with a lower activation energy."

Yeah. Thats the proper meaning, but "lowers the activation energy req." can also mean that since, there's an alternative pathway with a lower activation energy, the overall activation energy (because of the alternative pathway) would drop.

[jasonn93]

aahh, thanks alot guys! i guess i'll just go with the safe alternative

[Mao]

Do catalysts actually break the bonds in reactants or just weaken them so that there is a higher chance of successful collision? Thanks =]

Yeah, basically. Most of the time it makes the intermediate/transition state more stable, so reaction can occur more readily.

[jasonn93]

wait waitt.. so it weakens, not breaks, right? haha sorry

[Mao]

wait waitt.. so it weakens, not breaks, right? haha sorry

yes

[chansthename]

"A catalyst provides an alternative route for the reaction with a lower activation energy."

This is my stock standard answer if asked what a catalyst does, "provides an alternate reaction pathway which had a lower activation energy"

(and yes I realise it has little to do with the question asked)