1. TYPES OF ACID BASE TITRATION
& CURVES
“It is a quantitative analysis of
acid base by which known
concentration of an acid and
base i.e. titrant neutralize
concentration of an acid and
base i.e. titrand.”
2. Types of acid & base titration
• There are 4 types of acid & base titration .
Strong Acid & Strong Base HCl & NaOH
Strong Acid & Weak Base HCl & NH3
Weak Acid & Strong Base CH3COOH & NaOH
Weak Acid & Weak Base CH3COOH & NH3
TYPES OF ACID & BASE TITRATION
3. TITRATION CURVES
“A titration curve is a plot of pH
vs the amount of titrant
added.”
Graph:-
• pH = Y-axis
• volume of titrant = on X-axis.
Typically titrant is strong
completely dissociated acid or
base.
• These curves are useful for
determining the end points and
dissociation constant of acid
and base.
4. ACID BASE pH at Equivalence INDICATOR
Strong Strong = 7 Neutral Methyl orange
Phenolphthalein
Strong Weak <7 Acidic Methyl orange
Weak Strong >7 Basic Phenolphthalein
Weak Weak pH depends on
ka &kb of acid
and base
concentration
pH Of Acid Base Reaction At Its Equivalence
Point
5. 1- Strong Acid And Strong Base
Strong acid is taken in conical flask and titrated with
strong base.
• The strong acid is completely dissolved in water and
it produces H+ ions which are neutralized by OH- ions
present in the strong base solution.
HCl + H20 → H30+ +Cl-
At Equivalence point:-
• The H+ is completely neutralized by OH- ions.
• The # o f moles of NaOH= the # of moles of HCl
NaOH + HCl → NaCl+ H2O
6. In the graph :-
• Initially, it shows that the slow rise in pH and then
there is a sharp rise in the pH.
• This indicates that the neutralization is
completed.
pH at equivalence point =7
Example :- HCl & NaOH
7. 2- Strong Acid & Weak Base
Weak base is taken in the conical flask and a little
quantity of indicator is added. Then the
resulting solution is titrated with strong acid.
Graph:-
• The plot between pH and titrant shows
decrease in pH and then at the end point the
rapid pH drop and then remain constant.
• This indicates the completion of neutralization
by the formation of salts.
HCl + NH3 → NH4Cl
9. 3- Weak Acid And Strong Base
• The weak acid is taken in the conical flask and the
appropriate indicator is added. Then it is titrated with
strong base.
• When weak base is dissolve in water it partially dissociate
the H+ ions which is then neutralized by the strong base
that are produced the OH- ions.
CH3COOH +H20 → CH3COO- + H30+
Graph =
• Initially , shows the low pH and then after adding the
strong base , it shows the increase in pH and at the end
point it shows the sharp increase in pH .
• This indicates the completion of the neutralization.
CH3COOH + NaOH → CH3COONa + H20
10. • pH at equivalence point >7 (basic)
Example :- CH3COOH & NaOH
11. 4- Weak Acid And Weak Base
The weak acid is taken in the conical flask then add
the appropriate indicator and then titrate with the
weak base.
• It is titrated until the color change appears.
• The weak acid is partially dissociated and is
neutralized with the NH3 which is the weak base.
Graph=
• It shows the continuous decrease in the pH .
• Ph Change is not observed rapidly.
• End point is indicated by the formation of salt
CH3COOH + NH3 → CH3COONH4
12. At equivalence point, pH depends on ka &kb of
acid and base concentration
Example :- CH3COOH & NH3