Limiting Reactant and Percentage Yield Lab Report

Abstract

This laboratory experiment aimed to determine the limiting reactant and calculate the percentage yield in a reaction between Aluminum (Al) and Copper (II) Chloride (CuCl₂) using stoichiometry. The balanced chemical equation for the reaction is 2Al + 2CuCl₂ → 3Cu + 2AlCl₃. Through careful observations and calculations, it was concluded that CuCl₂ was the limiting reactant, and the percentage yield of copper was found to be 83.3%.

Introduction

The objective of this experiment was to identify the limiting reactant and determine the percentage yield in the reaction between Aluminum and Copper (II) Chloride.

The balanced chemical equation for the reaction is 2Al + 2CuCl₂ → 3Cu + 2AlCl₃. By utilizing stoichiometry, we aimed to make predictions and gain insight into the reactants' behavior during the reaction. The limiting reactant is the substance that is completely consumed, while the excess reactant remains after the reaction is complete.

Materials and Methods

Materials:

• 0.51g of Copper (II) Chloride (CuCl₂)
• 0.25g of Aluminum (Al)
• 2 100 mL beakers
• Stirring rod
• Filter paper
• Tweezers

Procedure:

1. Add approximately 50mL of water to the beaker containing aluminum foil and copper (II) chloride to initiate the reaction.
   Get quality help now

   

   Marrie pro writer

   Verified writer

   Proficient in: Chemistry

   5 (204)

   “ She followed all my directions. It was really easy to contact her and respond very fast as well. ”

   

   +84 relevant experts are online

   Hire writer

2. Record the initial color of the solution and the presence of any unreacted metal.
3. Observe and record any color changes as the reaction progresses, stirring occasionally with the stirring rod.
4. Once the reaction is complete, return the beaker and its contents to the instructor for proper disposal, avoiding disposal down the drain.
5. Set up the filtration apparatus to separate copper (Cu) from the aluminum chloride (AlCl₂) solution. Measure the mass of the dry filter paper before filtration.
   Get to Know The Price Estimate For Your Paper

   Topic

   Deadline: 10 days left

   Number of pages

   Email Invalid email

   By clicking “Check Writers’ Offers”, you agree to our terms of service and privacy policy. We’ll occasionally send you promo and account related email

   "You must agree to out terms of services and privacy policy"

   Write my paper

   You won’t be charged yet!

6. Carefully remove aluminum from the filter paper, rinsing it with water to prevent copper loss.
7. Dry the copper overnight and measure its mass when completely dry.

Observations

Calculations

Theoretical yield (TY) of copper (Cu) = 0.24g (calculated using stoichiometry)

Actual yield (AY) of copper (Cu) = 0.20g (measured)

Percentage yield = (AY / TY) * 100% = (0.20g / 0.24g) * 100% = 83.3%

Analysis

1. Based on our observations, it was evident that aluminum (Al) was present in excess as there were bits of unreacted aluminum remaining after all the copper (II) chloride (CuCl₂) had been consumed. This observation indicates that CuCl₂ was the limiting reactant in the reaction.
2. The prediction made before the experiment aligns with the experimental results, further confirming that CuCl₂ was the limiting reactant.
3. The calculated percentage yield of copper was found to be 83.3%, indicating that 83.3% of the theoretically expected copper was obtained in the experiment. This suggests that the reaction was moderately efficient, with some copper loss or other factors affecting the yield.
4. In conclusion, the experiment successfully identified the limiting reactant as CuCl₂ and determined the percentage yield of copper in the reaction with aluminum.

Conclusion

In this experiment, the limiting reactant was determined to be copper (II) chloride (CuCl₂), while aluminum (Al) was present in excess. The observed data supported this conclusion. Additionally, the percentage yield of copper in the reaction was found to be 83.3%. This experiment demonstrates the practical application of stoichiometry in predicting reactant consumption and product yield in chemical reactions.

Recommendations

For future experiments of this nature, it is recommended to further investigate the factors that may affect the percentage yield, such as reaction conditions, purity of reagents, and potential sources of copper loss. Additionally, exploring variations of the reaction and using different stoichiometric ratios could provide valuable insights into the reactants' behavior and their impact on yield.