Write a lab report on the estimation of copper by iodemetry including the aim,apparatus, procedures,observations,results and conclusion

Answer 1

Aim:

The aim of this experiment is to estimate the quantity of copper present in a given sample using iodometry.

Apparatus:

1. Analytical balance
2. Burette
3. Pipette
4. Conical flask
5. Beaker
6. Iodine solution
7. Sodium thiosulfate solution
8. Starch solution
9. Scissors
10. Funnel
11. Watch glass

Procedures:

1. Weigh a sample of the copper into a conical flask and dissolve it in a few drops of nitric acid.
2. Add distilled water to the flask and heat the solution until the copper is completely dissolved.
3. Cool the solution and transfer it to a beaker.
4. Add an excess of potassium iodide solution to the beaker and mix well.
5. Titrate the liberated iodine with standard sodium thiosulfate solution until the yellow color disappears.
6. Add a few drops of starch solution as the end point is approached, titrate until the blue color disappears.
7. Repeat the titration for accuracy.
8. Record the volume of sodium thiosulfate consumed in the titration.

Observations:

1. The initial blue color of the iodine solution turns yellow upon addition of the potassium iodide solution.
2. The presence of copper in the solution causes the liberation of iodine during the titration.
3. The blue color of the solution intensifies as more iodine is released and disappears once all the iodine has reacted.

Results:

Volume of sodium thiosulfate consumed in the titration: X ml

Calculations:

The amount of copper in the sample can be calculated using the following formula:

Copper content (%) = (X * M * 63.54) / (V * 100)

Where:
X = Volume of sodium thiosulfate consumed in the titration
M = Molarity of sodium thiosulfate solution
63.54 = Molecular weight of copper
V = Weight of the sample taken for analysis

Conclusion:

The experiment was successful in estimating the quantity of copper present in the given sample using iodometry. The calculated copper content can be used to determine the purity of the sample and further analysis of the sample.