If you mix two compounds together and you see no evidence of a chemical change what steps could you take to encourage these two compounds to chemically react

Most likely, you have to use a Catalyst, a chemical that helps the chemical reaction to be faster. Chemical reactions are sometimes very slow, as in this case. 

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.