titrationlabv4.doc - Acid-Base Titration Titration is a...

Acid-Base Titration
Titration is a laboratory technique that can be utilized to determine the
concentration of a certain substance. A standard solution having a known molarity is
titrated ‘against’ (reacted with) a solution of unknown concentration. Generally, an
indicator is utilized to signal the completion of the neutralization reaction.
The point at which the number of moles of hydronium ion (H
3
O + ) equals the
number of moles of hydroxide ion (OH
-
) is known as the equivalence point . The signal
that the equivalence point has been reached is a change in colour due to the presence of
the indicator. Theoretically speaking, once the equivalence point is reached, the
neutralization reaction is complete.
In this lab activity, you will titrate 0.1 M NaOH against an unknown
concentration of HCl in order to find its concentration.
Objectives :
1. To titrate a hydrochloric acid solution of unknown concentration with
standardized 0.10M sodium hydroxide.
2. To utilize the titration data to calculate the molarity of the hydrochloric acid.
Materials :
Apparatus:
Buret pipette Safety Goggles
Buret Clamp & Stand 3 Erlenmeyer Flasks Lab Apron
50 mL Beaker 100 mL Beaker 400mL Beaker
Reagents:
Standardized NaOH solution (0.10M)
Hydrochloric Acid solution Phenolphthalein solution (indicator)
CAUTIONS: The NaOH solution is corrosive to skin, eyes, and clothing.