A chemist is studying the effect of acid rain on the steel in bridges. why would she most likely use rate laws in this study?

The reaction between the acid rain and the metal comprising the bridge, in this case steel is an example of single replacement reaction which eats out the metal to produce other sorts of substance such as rusts and other deposits. She is most like to use the rate laws because this will allow her to identify up to what extent can the reaction proceed and the time it will take for all the metals to be eaten out.