Which of the following statements is TRUE about the law of conservation of energy? A.
A little energy is destroyed every time an energy transformation occurs.

B.
Energy can change form but the total amount of it remains constant.

C.
Because of the law of conservation of energy, it is possible for a machine to never need energy.

D.
Conservation of energy only occurs when some of the energy is converted to light.

thinking it would be d not too sure but i think it's right

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.