In science, jill is learning about solids such as brass, bronze, and steel. how should she classify these materials? a) pure substances b) state compounds c) homogeneous mixtures d) heterogeneous mixtures

How does a catalyst increase the speed of a reaction? a. the catalyst eliminates the activated complex stage, allowing products to form immediately. b. the catalyst lowers the energy level of the reactants, making it easier for them to react. c. the catalyst makes it easier for the activated complex to form, lowering the activation energy. d. the catalyst raises the energy level of the products, making the reaction finish sooner. reset next