Calculate Molarity-0.25 moles of sodium chloride is dissolved to
make 0.025 liters of solution

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.

D=m/v =57.9/3 = 19.3 g/cm^3

V=s/t  4.5 = 5000+15000+20000+5000t=45000/4.5t=10000sto convert divide by 360answer is 3 hours