1. Acids and Bases - Titration
19/01/12

2. Acid Base Indicator Litmus pH Revision exercise
An acid has a sour taste.
Lemon juice is an example of an acid.
An acid has a pH value between 0 and 7
Base
Indicator
Litmus pH

3. Stage 1
Use the 10cm3 pipette and pipette filler to measure out 20cm3 of sodium hydroxide (NaOH) and put it in the conical flask
Make sure to match the bottom of the meniscus with the scale on the pipette.

4. Stage 2 - Titration
Titrations are used to very accurately add a certain amount of an acid to a base. 1 2 3
Fill the burette accurately with 50cm3 of Hydrochloric acid (HCl)
Remember to line up bottom of meniscus

5. Stage 3 - Evaporation
Place the resultant solution from the final titration into an evaporating dish
Put the dish on a gauze on a tripod
Heat the dish with a Bunsen burner until all the liquid is gone

6. For our experiment we are using 1M HCl with a pH value of 0
To titrate hydrochloric acid (HCl) against sodium hydroxide (NaOH) and prepare a sample of salt NaCl
For our experiment we are using 1M HCl with a pH value of 0
And 1M NaOH with a pH value of 14
We add the HCl to the NaOH
What do you think will happen to the pH value of the resulting solution?

7. To titrate hydrochloric acid (HCl) against sodium hydroxide (NaOH) and prepare a sample of salt NaCl
Stage 1
Stage 2
Stage 3 1 2 3

8. Volume of HCl added (cm3)
Discussion of results
We have just performed a neutralisation reaction. The addition of the HCl lowered the pH of the solution to 7
Neutralisation
ACID + BASE = SALT + WATER
HCl + NaOH = NaCl + H2O
Titration No.
Volume of HCl added (cm3)
Can you think where this type of reaction might be useful in everyday life?