Calculate the
Ka of 0.3M solution
of acetic acids, HC2H302, at 25c.
where pH = 2.8

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.

C) electrons encircling a nucleus with neutrons and protons

16- counting by fours