How many moles are in 15.94g of water?
305,3 mol h20
1,063 mol h20
0,8856 mol h20
16,94 mol h20

Your answer would be 0,8856 mol H2O.

Molar mass of H2O is approximately 18 g/mol

15.94/18 = 0,8856 mol H2O

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.