Title: ACID BASE TITRATION.

Objectives: 1. To determine the concentration of acid using titration. 2. Skills of titration techniques.

Apparatus: 1. 250 volumetric flask 2. 10mL measuring cylinder 3. 25mL pipette 4. 50mL burette 5. 250mL beaker 6. 150mL conical flask 7. Retord stand 8. White tile 9. Stopwatch 10. Pipette bulb

Chemicals: 1. HCl solution 2. 0.1M NaOH solution 3. H2SO4 solution 4. Distilled water 5. phenolphthalein

Introduction.
An acid-base titration is the determination of the concentration of an acid or base by exactly neutralizing the acid/base with an acid or base of known concentration. This allows for quantitative analysis of the concentration of an unknown acid …show more content…

As more bases is added, the pink solution will remain for a longer time, when this occurs slow the addition of base so that only one or ½ drop of base at a time. 6. The flask is swirled on each addition. At the end point, one drop of base solution will turn the entire content of the flask to light pink. At this point, the final volume of the base is recorded to the nearest 0.01mL. 7. The experiment is repeat 2 times to ensure the reliability of the experiment. 8. All the conical flask is washed and rinsed with the unknown H2SO4. 9. All procedure are repeated using the unknown H2SO4.

Result.

Using HCl | | 1 | 2 | 3 | average | Volume of acid (mL) (±0.00) | 25.0 | 25.0 | 25.0 | 25.0 | Final volume of base (mL) (±0.000) | 9.70 | 19.70 | 29.70 | 19.70 | Initial volume of base (mL) (±0.000) | 0.00 | 9.70 | 19.70 | 9.8 | Volume of base used (mL) (±0.000) | 9.70 | 10.00 | 10.00 | 9.90 | Molarity of acid (M) | 0.04 | 0.04 | 0.04 | 0.04 | | | | | |

Using H2SO4 | | 1 | 2 | 3 | average | Volume of acid (mL) (±0.00) | 25.0 | 25.0 | 25.0 | 25.0 | Final volume of base (mL) (±0.000) | 19.50 | 39.60 | 59.30 | 39.47 | Initial volume of base (mL) (±0.000) | 0.00 | 19.50 | 39.60 | 19.70 | Volume of base used (mL) (±0.000) | 19.50 | 20.1 | 19.70 | 19.77 | Molarity of acid (M) | 0.04 | 0.04 | 0.04 | 0.04 | | | | | |

Calculation.

Discussion & Questions.

1) Why is