Acid-Base Neutralization
Reactions
Chem 12
Acid + Base  Salt + Water
• Orange juice + milk  bad taste
• Evergreen shrub + concrete  dead bush
• Under a pine tree + fertilizer  white powder
• HCl + NaOH  NaCl + HOH
salt
water
Acid-Base Neutralization
Reactions
HCl(aq) + NaOH(aq)  NaCl(aq) + H2O(l)
• The products of an acid-base
neutralization reaction are a salt made up
of the positive ion of the base (Na+) and
the negative ion (Cl-) of the acid, and
water.
• Remember, in writing the correct formula
for the salt, the total positive charge of
the ions in the salt must equal the total
negative charge of the ions in the salt.
• Make sure you write the correct formula
for the products, salt and water first, then
balancing the equation.
• The particles present in the HCl(aq) solution due
to ionization are
HCl(g) + H2O(l)  H3O+(aq) + Cl-(aq)
Or
HCl(g)  H+(aq) + Cl-(aq)
• The particles present in the NaOH(aq) solution
due to dissociation are
NaOH(aq)  Na+(aq) + OH-(aq)
• Therefore, the ionic equation for the
reaction is
H3O+(aq) + Cl-(aq) + Na+(aq) + OH-(aq) 
Na+(aq) + Cl-(aq) + 2H2O(l)
or
H+(aq) + Cl-(aq) + Na+(aq) + OH-(aq) 
Na+(aq) + Cl-(aq) + H2O(l)
• If we remove the spectator ions, Na+(aq)
and Cl-(aq), we are left with the net ionic
equation for the acid-base neutralization
reaction:
H3O+(aq) + OH-(aq)  2H2O(l)
H+(aq) +
Or
OH-(aq)
 H2O(l)
• Therefore, in an acid-base neutralization
reaction we can see that it is the
hydronium ion from the acid that reacts
with the hydroxide ion from the base to
produce neutral water.
• Since the hydronium ion gives the acid its
properties and the hydroxide ion gives the
base its properties, the acid-base reaction
has resulted in the neutralization of the
properties of both the acid and the base.
SAMPLE PROBLEM 1
For the acid-base neutralization of nitric
acid, HNO3(aq) and calcium hydroxide
Ca(OH)2(aq), write the balanced:
a) complete equation
b) ionic equation
c) net ionic equation
a) The complete balanced equation for
the reaction is
Ca(OH)2(aq) + 2HNO3(aq)  Ca(NO3)2(aq) + 2H2O(l)
b) The ionic equation is
Ca2+(aq) + 2OH-(aq) + 2H+(aq) + 2NO3-(aq) 
Ca2+ (aq) + 2NO3-(aq) + 2H2O(l)
c) The net ionic equation is
2OH-(aq) + 2H+(aq)  2H2O(l)
SAMPLE PROBLEM 2
For the acid-base neutralization of
perchloric acid, HClO4(aq), and potassium
hydroxide, KOH(aq), write the balanced:
a) complete equation
b) ionic equation
c) net ionic equation
a) The complete balanced equation for the
reaction is
HClO4(aq) + KOH(aq)  KClO4(aq) + H2O(l)
b) The ionic equation is
H+(aq) + ClO4-(aq) + K+(aq) + OH-(aq) 
K+(aq) + ClO4-(aq) + H2O(l)
c) The net ionic equation is
OH-(aq) + H+(aq)  H2O(l)