Summary

In this lesson, students will evaluate data from 16 simulated lab experiments that were designed to mirror the Recommended Labs from the College Board. Corresponding lab experiments and demonstration options have also been included for teacher reference. 

Grade Level

High School

AP Chemistry Curriculum Framework

This lesson plan supports the following unit(s), topic(s) and learning objectives:

• Unit 1: Atomic Structure and Properties
  • Topic 1.3: Elemental Composition of Pure Substances
    • 1.3.A: Explain the quantitative relationship between the elemental composition by mass and the empirical formula of a pure substance.
  • Topic 1.6: Photoelectron Spectroscopy
    • 1.6.A: Explain the relationship between the photoelectron spectrum of an atom or ion and: a. The electron configuration of the species. b. The interactions between the electrons and the nucleus.
• Unit 3: Properties of Substances and Mixtures
  • Topic 3.9: Separation of Solutions and Mixtures
    • 3.9.A: Explain the relationship between the solubility of ionic and molecular compounds in aqueous and nonaqueous solvents, and the intermolecular interactions between particles.
  • Topic 3.11: Spectroscopy and the Electromagnetic Spectrum
    • 3.11.A: Explain the relationship between a region of the electromagnetic spectrum and the types of molecular or electronic transitions associated with that region.
  • Topic 3.13: Beer-Lambert Law
    • 3.13.A: Explain the amount of light absorbed by a solution of molecules or ions in relationship to the concentration, path length, and molar absorptivity.
• Unit 4: Chemical Reactions
  • Topic 4.6: Introduction to Titration
    • 4.6.A: Identify the equivalence point in a titration based on the amounts of the titrant and analyte, assuming the titration reaction goes to completion.
  • Topic 4.7: Types of Chemical Reactions
    • 4.7.A: Identify a reaction as acid-base, oxidation-reduction, or precipitation.
• Unit 5: Kinetics
  • Topic 5.2: Introduction to Rate Law
    • 5.2.A: Represent experimental data with consistent rate law expression.
• Unit 6: Thermochemistry
  • Topic 6.4: Heat Capacity and Calorimetry
    • 6.4.A: Calculate the heat q absorbed or released by a system undergoing heating/ cooling based on the amount of the substance, the heat capacity, and the change in temperature.
  • Topic 6.9: Hess’s Law
    • 6.9.A: Represent a chemical or physical process as a sequence of steps.
• Unit 7: Equilibrium
  • Topic 7.2: Direction of Reversible Reactions
    • 7.2.A: Explain the relationship between the direction in which a reversible reaction proceeds and the relative rates of the forward and reverse reactions.
  • Topic 7.9: Introduction to Le Châtelier’s Principle
    • 7.9.A: Identify the response of a system at equilibrium to an external stress, using Le Châtelier's principle.
• Unit 8: Acids and Bases
  • Topic 8.5: Acid-Base Titrations
    • 8.5.A: Explain results from the titration of a mono- or polyprotic acid or base solution, in relation to the properties of the solution and its components.
  • Topic 8.9: Henderson-Hasselbalch Equation
    • 8.9.A: Identify the pH of a buffer solution based on the identity and concentrations of the conjugate acid-base pair used to create the buffer.
  • Topic 8.10: Buffer Capacity
    • 8.10.A: Explain the relationship between the buffer capacity of a solution and the relative concentrations of the conjugate acid and conjugate base components of the solution.
• Unit 9: Thermodynamics and Electrochemistry
  • Topic 9.8: Galvanic (Voltaic) and Electrolytic Cells
    • 9.8.A: Explain the relationship between the physical components of an electrochemical cell and the overall operational principles of the cell.

Objectives

By the end of this lesson, students should be able to

• Improve understanding of lab data analysis.
• Think critically about scenario-based questions, justifying responses with lab data.
• Demonstrate a strong performance for lab-based questions on the AP Chemistry Exam.

Chemistry Topics

This lesson supports students’ understanding of:

• Solutions
• Spectroscopy
• Beer’s Law
• Absorbance
• Concentration
• Conductivity
• Stoichiometry
• Chemical Reactions
• Net Ionic Equations
• Precipitation Reactions
• Combustion Reactions
• Decomposition Reactions
• Redox Reactions
• Half Reactions
• Percent Error
• Reaction Rates
• Rate Laws
• Catalysts
• Acids and Bases
• Titration Curves
• Titrations
• pH
• Indicators
• Buffer Solutions
• Buffer Capacity
• Ionic Bonding
• Covalent Bonding
• Metallic Bonding
• Hydrates
• Alloys
• Percent Composition
• Mixtures
• Chromatography
• Gas Laws
• Energy
• Enthalpy
• Calorimetry
• Equilibrium
• Le Châtelier’s Principle

Time

Teacher Preparation: Time will vary

• Teacher prep time will vary widely, depending on how many experiments you prepare versus using the supplied packet of simulated lab data.
• The labs take about 30 minutes each to prepare (16 lab possibilities = 8 hours maximum).
• The packets will take about 5-10 minutes to prepare.
  • Note: Some of the graphs and figures require a color copier. If that is not available for you, I have included the source data so that you can change the graphics.

Lesson: Time will vary

• If completing only the scenario-based examples, I suggest allowing for:
  • 20-30 minutes per scenario
•  If completing labs, I suggest allowing for:
  • 60 minutes per lab experiment
• The packet could be assigned for homework to supplement a classroom lab activity

Materials

• Student Packet Handout
  • If you are using the packet as sample data and models for the laboratory experiments, then all you need is one printed packet per student.
• Optional: If you have time to do short lab activities along with the provided packet, I have included suggestions for each of the 16 lab activities in the Teacher Notes section below.

Safety

• Note: The safety precautions will vary depending on if any labs and/or demonstrations are used, versus just using the student packet handout.
• Refer to the specific safety precautions listed in any lab or demonstration that is used. General lab guidelines should always be followed, including:
  • Always wear safety goggles when handling chemicals in the lab.
  • Students should wash their hands thoroughly before leaving the lab.
  • When students complete the lab, instruct them how to clean up their materials and dispose of any chemicals.
  • Always use caution around open flames. Keep flames away from flammable substances.
  • Always be aware of an open flame. Do not reach over it, tie back hair, and secure loose clothing.
  • Exercise caution when using a heat source. Hot plates should be turned off and unplugged as soon as they are no longer needed.
  • An operational fire extinguisher should be in the classroom.
  • When working with acids, if any solution gets on students’ skin, they should immediately alert you and thoroughly flush their skin with water.
  • When diluting acids, always add acid to water.
  • Students should wear proper safety gear during chemistry demonstrations. Safety goggles and lab apron are required.

Teacher Notes

• This Experimental Evidence Review is based on the 16 recommended labs from the College Board. The main ideas from each lab experiment have been used to create questions that a student could encounter on the AP Chemistry exam from those lab experiments.
• Links to AACT resources, that I suggest for demonstrations, labs, and lesson plans to use if time allows are included for teacher reference.
• This lesson contains sample data based on valid equations that govern the lab activities.
• You could also use this lesson in conjunction with the AP Chemistry Big Idea Review lesson plan that can be downloaded from the AACT resource library.
• The scenarios in the packet are NOT to be used as written for student lab experiments. The scenarios do not include SDS information nor do they list safety precautions for the experiment. 

If you have time to do short lab activities along with the provided packet, I have included some suggestions for each of the 16 lab activities below:

• Lab 1: Beers Law to Quantify Color
  • Conduct a serial dilution with a colored metal solution, like CuSO₄, and give the students an “unknown” to determine the concentration.
  • Example: Using Color to Identify an Unknown

• Lab 2: Analysis of an Alloy with Spectroscopy
  • Dissolve the alloy in nitric acid and use the color of the resulting solution to determine the concentration of copper in the original sample. This is easiest with an alloy of copper, like brass or bronze.
  • Example: Beer’s Law Discovered

• Lab 3: Stoichiometry and Predictive Precipitation
  • Conduct a demonstration of solubility rules, with various solutions to show the solubility rules. You could react various sodium polyatomic ion compounds with a metal solution to show solubility and exceptions.
  • Example: Precipitation Reaction

• Lab 4: Determination of Acid Concentration by Titration
  • Example: Exploring the Properties of Acids and Bases
  • Example: PhET simulations for acids and bases

• Lab 5: Components of a Mixture
  • Conduct a demonstration of a type of chromatography. Paper chromatography is easiest, since all you need is a coffee filter, markers, and a beaker of water to see the dyes in the marker separate into the component colors.
  • Example: Candy and Leaf Chromatography

• Lab 6: Ionic, Covalent, and Metallic Bonding
  • There are many properties of substances that can be explored here. Students create a list of physical/chemical properties that they believe would be different for ionic, covalent, and metallic substances. Then conduct the tests that would be appropriate.
  • Example: You Light Up My Life
  • Example: Ionic and Covalent Bonding

• Lab 7: Formula for a Hydrated Crystal
  • Dehydrate blue Copper(II) sulfate and calculate the formula for the hydrated crystal. This one is great because there is a blue-white color change that accompanies the dehydration.
  • Example: Formula of an Unknown Hydrate

• Lab 8: Redox Titration
  • There are a number of redox titrations options. I like food dye and bleach, since it is practical and applies to laundry that the students (hopefully) understand.
  • Example: Fine Art of Redox

• Lab 9: Separation of Mixtures
  • Separate a mixture of sand, salt, and pepper. The salt dissolves in the water and the peppercorns float, so the students can either decant them or filter the peppercorn from the decanted salt water.
  • Example: Test Tube Separation

• Lab 10: Factors that Affect the Rate of a Reaction
  • Teachers can conduct a demonstration with hydrogen peroxide, liquid soap, and potassium iodide catalyst. To show the effect of concentration, vary the hydrogen peroxide concentration. To show the effect of surface area, use a saturated solution of potassium iodide and solid salt. To show temperature, you can conduct the demo at room temperature and heat the flask of hydrogen peroxide.
  • Example: Rates of Reaction demonstration
  • Example: Reaction Rates simulation

• Lab 11: Determining Rate Law
  • A lab similar to the description presented in the scenario can take a lot of set-up time. This might be the best case of using data instead of conducting an experiment, in order to save time.
  • Example: PhET Reactions and rates Simulation
  • Related Lesson: Reaction Mechanisms

• Lab 12: Enthalpy and Calorimetry
  • There are a number of calorimetry experiments that can be done, such as, Enthalpy of Salt Dissolution or Hess’s Law. A demonstration with salts that dissolve in water to produce a cold solution, or a hot one can demonstrate the flow of heat.
  • Example: Hess’s Law Application

• Lab 13: Le Châtelier’s Principle
  • There are a number of demonstrations for Le Châtelier’s Principle.
  • Example: Le Châtelier’s Principle demonstration

• Lab 14: Strong vs. Weak Acid Titrations
  • In the sample experiment data, two titrations are performed with NaOH solution, while pH is monitored.
  • Example: How to Perform a Titration

• Lab 15: Recipe for the Best Buffer
  • There are many buffer demonstrations that teachers can perform. One would be to monitor the change in pH when a drop of strong acid is added to water vs. baking soda solution.
  • Example: Milk of Magnesia Magic

• Lab 16: Buffer Capacity
  • Example: Preparation and Evaluation of Buffers