2H2 (g) + O2 (g) ® 2H2O(g)
reactants product(s)
The above equation is an example
of a balanced chemical equation.
–“+” means “reacts with”
–the coefficients
show the relative quantity of atoms or molecules of the reactants
and products (1 being understood)
–the symbols
inside the brackets indicate the physical state of the pure substances
except “aq” which means aqueous, in solution (dissolved in water)
–“s” indicates solid, “l”
indicates liquid and “g” indicates gaseous
A balanced chemical equation
shows the same type and equal number of
atoms and charges on both sides.