Now the rate law is just an expression that relates the rate of a reaction to its react, change of reacting concentrations, rate constant and reaction orders. Now your rate constant is a proportionality constant that links the rate to these reactant concentrations, and your reaction orders well. These are just the exponent component for the given concentrations. Now they're determined mathematically with a chart which has given values or from a series of steps called a reaction mechanism.
Here we're not going to go into detail on reaction mechanisms just yet because pretty abstract. Later on we'll go in greater detail on what reaction mechanisms are and how we can use them to figure out our reaction orders. Now also what's important is that rate law ignores products because notice I only talked about the concentration of the reactants. I never mentioned concentrations of products because when it comes to rate law we ignore products altogether.
Now our rate law has its rate law expression which is rate equals K which is your rate constant times AXBY. Now A & B represent your reaction concentration or reactant concentrations. Here, if your chemical equation had more than two reactants then we continue we'd have CZ X and Y. These are your exponents or reaction orders. So just remember, your rate law is trying to connect the ideas of changes in concentration for your reactants, rate constant and reaction orders in order to find the overall rate of any given chemical reaction.