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# Particle Level Molarity Mark as Favorite (83 Favorites)

ACTIVITY in Concentration, Molarity, Molality, Kitchen Chemistry, Kitchen Chemistry - High School. Last updated February 14, 2023.

### Summary

In this activity, students are introduced to molarity at the particle level. Students will activate their prior knowledge by demonstrating their understanding of concentration by preparing several Kool-Aid drinks, and then applying that information at the particle level to various models.

High School

### NGSS Alignment

This activity will help prepare your students to meet the performance expectations in the following standards:

• Scientific and Engineering Practices:
• Developing and Using Models
• Using Mathematics and Computational Thinking

### Objectives

By the end of this activity, students should be able to:

• Explain the meaning of molarity in reference to the particle concentration in a solution.
• Use models to accurately represent the meaning of molarity.
• Determine the molarity of a solution using the molarity equation.

### Chemistry Topics

This activity supports students’ understanding of:

• Solutions
• Molarity
• Concentration
• Particle level

### Time

Teacher Preparation: 30 minutes

Activity: 50 minutes

### Materials (per group)

• 1 small packet of Kool-Aid Powder
• 2 cups
• Water
• Molarity card sort cards
• Calculator

### Safety

• 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.
• Do not consume lab solutions, even if they’re otherwise edible products.

### Teacher Notes

• Find out more about this Activity in an article the November 2017 issue of Chemistry Solutions.
• I use this activity as the opening to a solutions unit. First, I have my students make concentrated and dilute Kool-Aid solutions.
• Put students in small groups.
• Give each group a packet of Kool-Aid powder, water, and two cups.
• Without any additional instruction, tell students to make a cup of highly concentrated Kool-Aid and a cup of Kool-Aid that is weak in concentration. Typically, they easily do so.
• Students can communicate that the dark colored Kool-Aid is strong in concentration while the light colored Kool-Aid is weak. This is the macroscopic representation. I then ask the students to draw diagrams of Kool-Aid and water in the two cups (on a whiteboard, in a notebook, etc.). A typical student response is shown in the first image.
• I then ask students to add “particles” of Kool-Aid to their drawings. This typically results in the sketch being improved, such as shown in the second image.
• If you want to allow students to drink their Kool-Aid solutions, be sure to do so in a classroom rather than a lab environment. If this activity is done in the lab, students should not drink the solutions.
• Next, instead of giving the equation for molarity and having students calculate concentrations, students work with the particulate representation of molarity and look for patterns on their own so that they construct their own knowledge about determining concentrations of solutions.