Balancing Chemical Equations

What is Balancing? Writing a chemical equation so it has the same number of reactant atoms as product atoms Reactants = Products

Why do we Balance?? We must follow the Law of Conservation of Mass! (remember? Matter can’t be created or destroyed)

How do you balance an equation? Hydrogen gas reacts with chlorine gas to produce hydrochloric acid. Write the equation first: H2(g) + Cl2(g)  HCl Count the atoms of each element on each side of the equation: 2 H + 2 Cl  1 H and 1 Cl

How do you balance an equation? H2(g) + Cl2(g)  HCl 2 H + 2 Cl  1 H and 1 Cl The numbers of H and Cl are NOT equal so this equation is unbalanced.

How do you balance an equation? H2(g) + Cl2(g)  HCl To balance, use coefficients ___H2(g) + ___Cl2(g)  ___HCl

How do you balance an equation? ___H2(g) + ___Cl2(g)  ___HCl add a coefficient of 2 In front of HCl ___H2(g) + ___Cl2(g)  _2_HCl

Check Yourself: Balance the following equation: ____N2 + ____H2  ____NH3