:Sources of Error that Impact the Percentage Yield

[Strawberry123]

URGENT:Sources of Error that Impact the Percentage Yield

So my question is:
1. What sources of error in the experiment would affect the percentage yield of reaction?
2. In what ways this experiment could be improved?

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This is my chem lab on the reaction 2Al + 3CuCl2 --> 3Cu + 2AlCl3.

Purpose: to find the percentage yield of copper in the reaction.

Procedure:
1. Add enough distilled water to dissolve the 0.51 g of CuCl2 (s) in the beaker.
2. Record the colour of the resulting solution.
3. Measure out 0.25 g of the aluminum and add this to your solution.
4. Leave the beaker on your lab desk and allow the reaction to go to completion.
5. When the reaction is completed, record your observations.
6. Use the forceps to collect all copper formed. Carefully transfer the copper to a beaker and rinse the copper with water.
7. Pour off as much of the rinse water as possible. Spread the copper on the bottom of the beaker.
8. Cover the beaker containing the wet copper with a watch glass and gently heat the beaker on a hot plate to dry the copper. Reduce heat if the copper begins to turn black.
9. When the copper is dry completely, determine the mass of copper.


Thanks Millions! Please help! I'd really appreciate it! =]

 

[Nino MMP]

Answer: 1. Sources of error that could affect the percentage yield of reaction include incomplete dissolution of the reactants, incomplete reaction due to insufficient temperature or time, and loss of reactant or product due to improper technique.2. The experiment could be improved by ensuring the reactants are completely dissolved before beginning the reaction, using a hot plate set to the correct temperature for the reaction, and using proper technique to ensure all reactant and product are collected and weighed accurately.