Which elements have two valence electrons? A. Carbon
B. Magnesium
C. Fluorine
D. Sodium

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.

Ok so co(g) is not pronoused that. the only clue is that youpronouse it the oppisote way.