How is the Periodic Table helpful to scientists?

the table is useful for modern students and scientists because it helps predict the types of chemical reactions that a particular element is likely to participate in. ... The table tells each element's atomic number and usually its atomic weight. The typical charge of an element is indicated by its group.

Rate law for this reaction israte of the reaction = k[a]²[b].second order in a  means concentration of a in power of two, and  first order in b means concentration of b in power of one.