Stoichiometry Lab Report PDF

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Summary

Chemistry Lab Chapter 7, Stoichiometry Lab report...

Description

Single Replacement Reaction Stoichiometry and Percent Yield Background (0.5 points) List the six steps to solving stoichiometric calculations found in the background:

Write a balanced chemical equation for reaction Calculate the number of moles of each reactant. Determine if one of the reactants is a limiting reactant. Calculate number of moles of product produced based on number of moles of limiting reactant and balanced chemical equation. 5. Convert step#4 answer to grams 6 Calculate percent yield after determine actual yield experimentally

1. 2. 3. 4.

Materials Needed (0.5 points) List the materials from the background of the lab

Aluminum, Foil filter, Funnel, 2filter paper, Spoons, weighing boats, Graduated Cylinder, Electronic balance, Pipets, Plastic beaker, Ruler 6”, paper towels, Sodium chloride, NaCl and Table salt.

Video (0.5 points) Copy and paste the link to the you tube video for the Single Replacement Lab Demonstration

https://www.youtube.com/watch?v=NWUH2sI7Sko

Safety (0.5 points) What are the safety concerns for this lab according to the background?

The copper sulfate solution is toxic when ingested and is a tissue irritant. Wash hands thoroughly after handling the copper sulfate. Don’t eat, drink or chew gum while performing this activity. Wash hands with soap and water after performing activity. Clean up work area with soap and water. Keep pets and children away when performing lab.

Single Replacement Reaction Stoichiometry and Percent Yield

Pre-laboratory Questions (5 points total, 1 point each) 1. Write the balanced equation for the reaction of aluminum with copper(II) sulfate solution.

2Al(s)+3CuSO4(aq)3Cu(s)+Al2(SO4)3(aq) 2. What is the mole ratio of the reactants to one another and what is the mole ratio of Al metal to Cu Metal?

2:3 3. How many moles of aluminum will be required to produce 0.45 moles of copper metal?

2*0.45/3=0.3 moles Al 4. How many grams of aluminum will be required to produce 4.5 g of copper metal?

2*27/3*63.5=0.283

5. Based on the information in the procedure, why does the copper metal have to be completely dry before the yield is calculated?

The mass of the liquid is not included with the measurements

Single Replacement Reaction Stoichiometry and Percent Yield Please Type Your Data Here! (3 points) Data Table 1: Single-Replacement Reaction of Al and Copper Sulfate Sample Results Balanced Chemical Equation Volume of 1 M CuSO4

100.0ml

Mass of Al foil

1.56g

Moles CuSO4

0.1moles

Moles of Al

0.0578

Moles Cu Product based on Starting CuSO4

63.55

Moles Cu Product based on Starting Al

1.52

Limiting Reactant

Al

Theoretical Yield of Cu in Moles

1mol/cu

Theoretical Yield of Cu in grams

6.35g

Actual Yield of Cu in grams Percent Yield of Cu

6.76g

72%

Sample Results

Sample Results

Single Replacement Reaction Stoichiometry and Percent Yield Pictures (5 points total, 2.5 points each) Upload picture of Activity One Set Up. Include all of the required materials in your picture

Upload Picture of Step 11: Gravity Filtration. Show the filter paper after the solution has been filtered.

Single Replacement Reaction Stoichiometry and Percent Yield

Laboratory Questions (10 points total, 1 point each) 1. Describe the appearance of the copper(II) sulfate solution and the aluminum foil before the reaction starts.

There was light blue liquid, and the aluminum foil was still a regular color 2. Describe your observations of the solution during the reaction.

The aluminum began to sizzle as I was stirring it. It was smoking and the measuring cup was getting hot 3. Describe the appearance of the solution and any solids after the reaction. The solution was brown and sandy at the bottom of the beaker 4. Describe the appearance of the solid after it is dried.

A dark brown copper color 5. Was all of the copper(II) sulfate reacted in this lab? Explain your answer both with observations and calculations.

Yes, it was a brown copper color after all the foil was mixed in with the liquid. 2*27/3*63.5=0.283

6. Identify the excess and limiting reactants.

Al was the limiting reactant and CuSo4 was the excess reactant 7. Identify two aqueous substances that were washed away from the final solid.

CuSo4 and Al2(So4)3 was aqueous substances 8. If the solids were not washed before drying, how would this change the copper metal yield?

The solids can mix with the copper and increase the weight

9. If the copper is not completely dried, how would this change the yield of copper metal?

It will change the weight of the copper metal because it’s not fully dry/solid.

Single Replacement Reaction Stoichiometry and Percent Yield 10. Explain why the percent yield was not 100%. What are some sources of error?

The sample was not dry enough it still contained some liquid in it...