PLEASE HELP ASAP ILL GIVE BRAINIEST Do you place an item in the autoclave before or after washing it?

Wash it first to remove obvious soil or residue.

Then put it into the autoclave to sterilize it.

b. the carbon cycle ensures living things have a source of hydrogen

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.