Building Inquiry in AP® Chemistry Labs

Carolina Biological Supply Company

AP® is a trademark registered and/or owned by the College Board®, which was not involved in the production of, and does not endorse, these products.

New AP® Chemistry Curriculum Framework

•  Focus on inquiry

•  6 Big Ideas:

-Atoms -Chemical and Physical Properties

-Changes in Matter -Rates of Chemical Reactions

-Thermodynamics -Chemical Equilibrium

•  Learning objectives paired with science practices

•  16 recommended experiments (6 inquiry based)

AP® Chemistry Has Changed

How can Carolina help you?

AP® is a trademark registered and/or owned by the College Board®, which was not involved in the production of, and does not endorse, these products.

16 kits to cover 16 recommended experiments

2 teaching approaches: guided and inquiry

•  Big Idea assessment questions modeled on the AP® Chemistry Exam free-response questions

•  Detailed preparation and procedure steps for the inquiry activity

•  Grading rubric for assessing the inquiry activity

•  An experimental design template based on the scientific method  

What Does Carolina Offer?

Carolina has a history of creating inquiry activities

AP® is a trademark registered and/or owned by the College Board®, which was not involved in the production of, and does not endorse, these products.

Carolina Chemonstrations® for AP® Chemistry: •  Each kit includes 2 to 4 demos for a visual

representation of the Big Idea •  Enough materials in each kit to perform the

demos at least twice •  Students create particle-level diagrams or

models to demonstrate their understanding of concepts

•  Data analysis and Big Idea questions help students think critically about the topics

What Does Carolina Offer?

6 new demonstration kits for the 6 Big Ideas of AP® Chemistry

 

Demos are great to introduce or review a Big Idea

AP® is a trademark registered and/or owned by the College Board®, which was not involved in the production of, and does not endorse, these products.

1.  Inquiry Chromatography Activity

2.  Reaction Rates Demos

3.  Colorful Buffer Guided Activity

Workshop Overview  Sample 3 Laboratory Investigations

Laboratory Investigation 1 •  Big Idea 2: Chemical and physical properties of

materials can be explained by the structure and the arrangement of atoms, ions, or molecules and the forces between them.

•  Essential Knowledge 2.A.3: Solutions are homogenous mixtures in which the physical properties are dependent on the concentration of the solute and the strengths of all interactions among the particles of the solutes and solvent.

•  Learning Objective 2.10: The student can design and/or interpret the results of a separation experiment (filtration, paper chromatography, column chromatography, or distillation) in terms of the relative strength of interactions among and between the components.

Laboratory Investigation 1

•  Investigate different solvents and solvent combinations to determine the best separation of dyes

•  Identify FD&C dyes in Kool-Aid® using paper chromatography

Chromatography as an Analytical Tool

1.  Place a small amount of solvent in the tube. 2.  Place a pin through the top of strip. 3.  Hang strip in test tube. 4.  Adjust pin so sample “spots” are above the

solvent.

Procedure

Laboratory Investigation 1 Chromatography Setup

Laboratory Investigation 2

•  Big Idea 4: Rates of chemical reactions are determined by the details of the molecular collisions.

•  Essential Knowledge 4.A.1: The rate of a reaction is influenced by the concentration or pressure of the reactants, the phase of the reactants and products, and environmental factors such as temperature and solvent.

•  Learning Objective 4.1: The student is able to design and/or interpret the results of an experiment regarding the factors (i.e., temperature, concentration, surface area) that may influence the rate of a reaction.

Demonstration Blue Bottle Reaction

Varying Reaction Rates with Temperature

In its reduced state, methylene blue is colorless (MBred). When fully oxidized, it is blue (MBox).

MBred + O2 à MBox (Fast Step)

colorless blue As the solution sits, it is slowly reduced by alkaline glucose to its colorless form (MBred).

MBox + glucose + NaOH à MBred (Slow Step) blue colorless

Increasing the temp while keeping concentrations constant speeds the conversion rate of the dye from blue to colorless.

Demonstration Sucrose Combustion

Varying Reaction Rate with a Catalyst

Carbon acts as a catalyst for the combustion of a sugar

cube.

carbon C12H22O11(s) + 12O2(g) -------> 12CO2(g) + 11H2O(g) + heat

Laboratory Investigation 3 •  Big Idea 6: Any bond or intermolecular

attraction that can be formed can be broken. These two processes are in a dynamic competition, sensitive to initial conditions and external perturbations.

•  Essential Knowledge 6.C.2: The pH is an important characteristic of aqueous solutions that can be controlled with buffers. Comparing pH to pKa allows one to determine the protonation state of a molecule with a labile proton.

•  Learning Objective 6.18: The student can design a buffer solution with a target pH and buffer capacity by selecting an appropriate conjugate acid-base pair and estimating the concentrations needed to achieve the desired capacity.

Laboratory Investigation 3

Procedure 1.  Prep—Using the calculations provided on the

activity sheet, prepare buffer solutions with pHs of 3.7, 4.7, and 5.7.

2.  Follow the activity sheet to investigate how the addition of acid or base affects buffers of different pH.

Preparation of a Buffered Solution Investigate buffer solutions by working in teams to prepare buffered solutions with designated pHs and investigate the effect of concentration on buffer capacity.

Sample Data/Observations and

Analysis Initial Color/pH

Color/pH after 1 drop HCl

Color/pH after 1 drop NaOH

Color/pH after 10 drops NaOH

0.1 M Acetic Acid

pink <4 pink <4 pink <4 pinkish orange 4.5

Water yellow 6 pink <4 blue 8 blue 8

0.1 M Sodium Acetate

green 7 yellow 6 blue 8 blue 8

3.7 Buffer pink <4 pink <4 pink <4 orange 5

4.7 Buffer orange 5 orange 5 orange 5 yellow 6

5.7 Buffer yellow 6 yellow 6 yellow 6 blue 8

Laboratory Investigation 3—Results

Laboratory Investigation 1—Results

®  

What did you learn? •  Chromatography activity

•  Factors affecting reaction rate

•  Colorful buffer inquiry activity

Discuss how to transition •  Big Ideas

•  Learning objectives

Workshop Summary  

Carolina™ Chemistry Resources

Apps for iPad®, iPhone®, and iPod touch® Videos

Electronic newsletter