You burn solid magnesium in excess oxygen to form magnesium oxide. If you started with 12.3 grams of magnesium (MM=24.3 g/mol) and end up with 20.4 grams of magnesium oxide (MM=40.3 g/mol), how much
oxygen was used in the reaction?

The equation below shows a chemical reaction. a + b + heat —> c + d according to the law of conservation of energy, which statement is true? a. the reactants absorb heat because they have less energy than the products. b. the products release heat because they have more energy than the reactants. c. the reactants generate heat because they have more energy than the products. d. the products require heat to form because they have less energy than the reactants.