2. What is the Law of Conservation of mass?
10 points
CHA
+ 202
CO2
+ 2H20
O Mass is created in a chemical reaction
ONew chemicals formed from a chemical reaction have a larger overall mass than the
original reactants
OMass is created in a physical change
OMass is never created or destroyed
need answer please

How has the scientific community addressed the safety of chemicals? a. chemicals are repeatedly tested, even those that have existed for a long time. b. existing chemicals are tested if they have never been tested before. c. chemicals are tested if they are suspected to have caused a problem. d. only new chemicals are tested.

Can someone me with questions 12 and 13 plz.

Match the formula for the following compound:   magnesium sulfate heptahydratemgs·7h2omg2so4·7h2omg(s o4)2·7h2omgso4·7h2o