State three uses of oxidation number

Which statement is best described as a atom

Areaction is first order with respect to reactant x and second order with respect to reactant y. which statement describes the rate law for this reaction?

Energy defines the different "states" of matter. in no more than 3 sentences, describe the amount of kinetic energy that each of the 3 states of matter possesses and relate that to the atom/molecular motion of each "state".