Asalad including lettuce, tomatoes, and onions would be classified as a a) compound b) element c) mixture d) solution

C) mixture

Explanation:

A mixture can be define as a combination of two or more substances in which the identity of each substances is retained. In a salad lettuce, tomatoes and onions are separate entities which are combined to form a mixture that is salad.

Mixture

Explanation:

A salad can be defined as plate full of different kinds of vegetables and fruits which are edible.

The plates contains tomatoes which are different in chemical composition, lettuce which is also different in chemical composition and onions which are all mixed together.

Elements having different chemical composition when combined together is known as a mixture.

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.