A 1.60 g calcium supplement contains 37.8 Ca by mass. the calcium is present in the supplement as CaCO3 (molar mass 100.09 g/mol) how many grams of CaCO3 are in the calcium supplement

Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

Which of the following are correct values for the ideal gas laws constant r

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.