1. Titration Of A Strong Base With A Strong Acid Chemistry Lab, Sec: 216
Dr. Tabassum Ashfaq.
Fatima AL-Juraib
Safa AL-Brahim
Samar basham
Hadeel AL-Babtain

2. Outline: Introduction Objective Equipments Procedure Calculations
Conclusion

3. Introduction
The purpose of a strong acid-strong base titration is to determine the concentration of the acidic solution by titrating it with a basic solution of known concentration, or vice-versa, until neutralization occurs. As both the acid and base are strong (high values of Ka and Kb), they will both fully dissociate, which means all the molecules of acid or base will completely separate into ions. At the equivalence point, equal amounts of H+ and OH- ions will combine to form H2O, resulting in a pH of 7.0 (neutral). The pH at the equivalence point for this titration will always be 7.0, note that this is true only for titrations of strong acid with strong base. In addition, the anion (negative ion) created from the dissociation of the acid combines with the cation (positive ion) created from the dissociation of the base to create a salt. Therefore, the reaction between a strong acid and strong base will result in water and a salt.

4. Objective
To determine the molarity of hydrochloric acid in a given sample.
To learn lab skills to prepare and liquefaction a standard solution in order to find the strength of an acid or a base solution.

5. Strong Acids and Bases:
Table 1.0
Table 1.0lists common strong acids and strong bases, it is wise to memorize this table as this will be useful in solving titration problems. The acids and bases that are not listed in this table can be considered weak. Note that the strong bases consist of a hydroxide ion (OH-) and an element from either the alkali or alkaline earth metals.
Acids
Bases
HCl
LiOH
HBr
NaOH HI
KOH
HClO4
RbOH
HNO3
CsOH
H2SO4
Mg(OH)2
Ca(OH)2
Sr(OH)2
Ba(OH

6. Equipments 5ml volumetric acid. Pipette.
50ml burette and a burette holder.
Two 250ml Erlenmeyer flasks.
Hydrochloric acid.

7. Equipments .1M NaOH. Phenolphthalein indicator. Distilled water.
Funnel.

8. Procedure
In a conical flask add about 25 cm3 of Hydrochloric acid using a pipette ,
and then add 2 -3 drop of phenolphthalein indicator.
(Using a funnel and a beaker) fill the burette with Sodium Hydroxide solution till it reaches zero mark.
Add the sodium hydroxide solution to hydrochloric acid in a small swirling after each addition.

9. Keep adding, you can see that the solution turn into pink color,
keep swirling until the hydrochloric acid turns pink,
when the pink color does not go away and remains pink, at this point it's called the endpoint.

10. Keep repeating the titration till you get values close to each other.
Using the same steps, you can determine the unknown sample of hydrochloric acid using sodium hydroxide.
Cautiously add this volume of hydrochloric acid to another 25 cm3 of sodium hydroxide solution to create a neutral solution.
Now using an evaporating dish put the solution on Bunsen burner flame
Put it down till it disappears in a crystallizing dish to produce a white crystalline solid.

11. Strong Acid
An acid that is completely ionized in aqueous solution. This means when the strong acid is placed in a solution such as water, all of the strong acid will dissociate into its ions, as opposed to a weak acid. The general equation of the dissociation of a strong acid is:
HA(aq) --> H+(aq) + A-(aq)
(The H represents hydrogen and the A represents the anion of the acid)
Strong Base
A base that is completely ionized in aqueous solution. This means when the strong base is placed in a solution such as water, all of the strong base will dissociate into its ions. The general equation of the dissociation of a strong base is:
XOH (aq) --> X+(aq) + OH-(aq)
(The OH represents hydroxide and the X represents the cation of the base)

12. Calculations Trial 2 Trial 1 4.3 ml 4.6 ml
Starting burette reading (mL)
16.7 ml
48 ml
Endpoint burette reading (mL)
13.3 vml
13.4 vml
Endpoint volume of NaOH solution (V mL) L L
Average volume in litres
mol
mol001335
Moles of NaOH= V(L) x molarity of NaOH
moles HCl
Moles of hydrochloric acid= moles of NaOH x 1mol hydrochloric acid , 1mol NaOH
moles\L
Molarity of hydrochloric acid= moles of HCL,Vol of sample used ( in litres)

13. Conclusion
Titration of a strong base with a strong acid experiment taught us how to differentiate between bases and acids and how to find the strength of each of them, it also taught us the calculations used to find the molarity of hydrochloric acid in a sample and the methods used to titrate acids and bases. The experiment also taught us how to use indicators and learn what each of them indicate.

14. thank you