Month: June 2023
CC-Foods
Core-comps
Chemistry Lab Project – Base Identification Project
Determining the Concentration of Oxalic Acid Hydrate Solution
Introduction:
In this lab, we will determine the concentration of an oxalic acid hydrate solution through a titration process. Oxalic acid is a diprotic acid that forms a hydrate compound with water molecules. By titrating the solution with sodium hydroxide (NaOH) solution, we can determine the concentration of oxalic acid hydrate.
Materials:
- Oxalic acid hydrate (C2H2O4·nH2O) – 0.4 g
- Unknown base – 10 mL
- Phenolphthalein indicator solution
- Burette
- Pipette
- Beakers
- Flask
- H2O 100 mL
- Graduated cylinder
- Magnetic stirrer
- Safety goggles
Procedure:
- Safety Precautions:
– Put on safety goggles throughout the experiment.
– Handle all chemicals with caution and avoid contact with eyes or skin.
– Be careful walking around when bringing chemicals to your station (be aware of your surroundings)
- Preparation of Oxalic Acid Hydrate Solution:
Weigh 0.4 g of oxalic acid hydrate (C2H2O4·H2O).
Dissolve the weighed oxalic acid in 100mL of H2O to make a solution with the concentration of 0.04
Make sure to weigh the 100 mL of H2O in a beaker
Stir the solution until the compound is completely dissolved.
Note the volume and calculate the molarity (concentration) of the oxalic acid hydrate solution.
- 3. Titration Procedure:
– Rinse a burette with a small amount of unknown base, making sure it is filled with the solution.
– Using a pipette, measure 10 mL of the prepared oxalic acid hydrate solution into a clean flask.
– To do this add a small amount of acid and roll in around the flask to clean it.
– Add a few drops of phenolphthalein indicator to the flask.
– Place the flask on a white tile or a piece of white paper to easily observe color changes.
– Start the titration by adding base drop by drop into the conical flask while swirling the flask gently.
– Continue adding the unknown base until a permanent pink color is obtained, indicating the completion of the reaction.
– Note the volume of unknown base used.
Table:
Trial 1 | Trial 2 | Trial 3 | |
How many mL are in the burette | 40 ml of unknown base | 27.5 mL | 34.5 mL |
Final reading of the burette | 27.5 ml | 44.9 mL | 51.8 |
Amount of acid used | 10 mL | 10 ml | 10 mL |
Volume of base used | 12.5 mL | 17.9 mL | 17.3 mL |
Amount of phenolphthalein indicator solution drops used | 3 drops | 4 drops | 4 drops |
Average volume of base in mL | 15.9 mL |
- 4. Repeat:
– Repeat the entire titration procedure two more times to obtain a reliable average value for the concentration of oxalic acid hydrate.
0.4g C2H204 (2H2O) × 1 mol ÷ 126g = 0.00317 mol ÷ 0.100L = 0.03
- Identifying The Base Lab
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- Bunsen burner
- Materials:
-
- Q-tips
- Flint striker
- Tweezers
- Beaker
- 20mL of unknown solution
Safety Procedure:
- Always wear safety glasses
- Tie up hair and roll up sleaves if necessary
Preparation:
- Set up Bunsen burner on a empty countertop and connect it to the gas.
- Turn on gas.
- Light burne4r with flint striker
- Make the flame your desired height.
Actual Identification Process:
- Take a Q-tip and dip it in the dissolved acid that’s in the beaker.
- Carefully use the tweezers to pick up the Q-tip and hold it over the flame.
- Once it starts burning identify and record the colour the flame changes to
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- 20mL of unknown solution with Q-tips over Bunsen burner
- Notes:
-
- The flame had turned orange/red (brick red) which means it is Calcium
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