It has to have a molecular geometry where the bond dipoles do not cancel.

7is b8 is d9 is c10 is a11 is d

It was ernest rutherford

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.