To check whether an equation is balanced, .

a. add the number of reactants to the number of products
b. make sure the masses of the reactants and products are the same
c. count the number of each type of atom on each side
d. check to see if the reaction is endothermic or exothermic

Energy is usually only shown with the products in an equation for .

a. an endothermic reaction
b. a synthesis reaction
c. an exothermic reaction
d. activation energy