For the following reaction:___ NH3 (g) + ___O2 (g) → NO (g) + H2O (g) a) Balance the reaction.
b) If a reaction is started with 1.50 g of ammonia (NH3) and 1.85 g of oxygen
how much nitrogen monoxide is formed, in grams?
c) Which reactant is the limiting reactant, and which is the excess reactant?
d) How much of the excess reactant is left over, in grams, after the reaction is
complete?

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.