The modern periodic table is arranged in order of increasing atomic

Cr(oh)3 -> cr(3+) + 3oh-

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.