a) A catalyst such as chlorophyll must be present for some reactions to take place.b) A catalyst such as chlorophyll is not one of the products of a chemical reaction.c) A catalyst such as chlorophyll is not a substance that is used or changed in a chemical reaction.
the way these choices are written they are all true but the answer could be B
Perky, I doubt that it would be B because everything could be said to be the result of a chemical reaction. I think the answer is C because you could paraphrase it to say; chlorophyll is a substance that does not participate in any chemical reactions, which is of course, not true.
It's not C, catalysts are not used up or changed in a chemical reaction, otherwise they would be part of the reaction. Technically B isn't right either because chlorophyll IS the result of a chemical reaction, a bunch of very complex reactions, how else would it come into existence? However I believe this is the answer you're looking for since I'm being too picky... Isn't not A, catalysts do not cause reactions to occur that wouldn't otherwise, they do speed them up considerably though, to the point of it seeming like it must be present for the reaction to take place since it would be so incredibly slow if it wasn't there, but I'm being to picky again... So I would say B.
A catalyst is something that speeds up a reaction by lowering it's activation energy, that is, minimum amount of energy required for a reaction to occur. Catalyst is added to reaction that have a very high activation energy, and in normal situation reaction will proceed very slowly and too much time is consumed to get any considerable amount of product. The reaction occurs nevertheless. Chemists are usually not concerned with the catalyst, as it is present both in the reactant side and product side unaltered, they are more concerned with the final (new) product formed from the reactants. Since catalyst speeds up a chemical reaction without being permanently altered therefor the answer is C.
(c) fairly catalyst varies the path of reaction or u can say mechanism of reaction in which activation ability receives decrease hence of which fruitful collisions occurred at extremely decrease temperature so greater beneficial opportunities for molecules to bypass activation complicated a catalyst is a substance that lowers the activation ability of a chemical reaction yet itself final unchanged in the process the time of the reaction
