Lab Report: Determining Percent Yield in a Chemical Reaction

Purpose:

To find out the percent yield of copper in the reaction between copper sulfate (CuSO4) and Iron (Fe).

Materials:

Balance

100-mL beaker

250-mL beaker

Bunsen burner

Copper sulfate crystals

Glass stirring rod

100-mL graduated cylinder

Iron filings

Ring stand and ring

Wire gauze

Procedure:

1. Record mass of clean 100-mL beaker.

2. Add 8.0 grams of copper sulfate crystals to beaker.

3. Add 50.0 milliliters of distilled water to the crystals.

4. Put wire gauze on ring on ring stand, and place the lighted Bunsen burner underneath it. Heat the crystals and water, but do not boil.

5. Stir until completely dissolved, then remove burner.

6. Add 2.24 grams of iron filings a little at a time to the hot solution. Allow the beaker to cool for 10 minutes.

7. Decant the liquid into a 250-mL beaker and do not disturb the solid at the bottom of the beaker.

8. Add about 10-mL of water to the solid and stir vigorously. Allow the solid to settle and decant again.

9. Spread the solid over the bottom and allow to dry.

10. After it is completely dry, mass the beaker and the solid copper. Record.

Data and Observations:

Mass of empty beaker 67.33 g

Mass of beaker plus copper 69.43 g

Actual yield of copper 2.1 g

Expected yield of copper 2.54 g

Percent yield of copper -17.32%

Calculations:

Actual yield of copper = 69.43 g - 67.33 g = 2.1 g

Percent yield of copper = 2.1 g Cu - 2.54 g Cu

2.54 g Cu

Conclusion:

The percent yield of copper is