In this activity, students will define terms related to various kinds of pure substances and mixtures, as well as analyze and draw particle diagrams.
Middle and High School
This activity will help prepare your students to meet the performance expectations in the following standards:
- MS-PS1-1: Develop models to describe atomic composition of simple molecules and extended structures.
- Scientific and Engineering Practices:
- Developing and Using Models
By the end of this lesson, students should be able to
- Define terms related to pure substances and mixtures
- Classify particle diagrams as representing elements, compounds, or mixtures thereof
This lesson supports students’ understanding of
- Elements and Compounds
Teacher Preparation: 10 minutes
Lesson: 30-45 minutes
- Student handout
- No specific safety precautions need to be observed for this activity.
- This activity would be a good follow-up to the Classifying Matter animation
- There are several ways you could scaffold this activity for different ability levels:
- Provide the definitions in Part 1 and ask the students to match them, or to remove some of the terms. You could also ask students to supply a real-world example of each term.
- Remove some of the particle diagrams from Part 2 so that there is only one example per term/all terms are used exactly once.
- In Part 4, when students check their answers with the teacher, you may want to circle/mark any that were originally incorrect so that when they are asked to explain their mistakes you know whether or not they had made any mistakes to begin with and which questions those were.
For the Student
Part 1: Definitions
Define the following terms:
a. Pure substance:
e. Homogeneous mixture:
f. Heterogeneous mixture:
Part 2: Label Particle Diagrams
Label the particle diagrams below with the letter of one of the following categories. (Categories may be used once, more than once, or not at all):
|a. Element||c. Mixture of Elements|
|b. Compound||d. Mixture of Elements and Compounds|
|e. Mixture of Compounds|
|1. ____________||2. ____________|
|3. ____________||4. ____________|
|5. ____________||6. ____________|
|7. ____________||8. ____________|
Part 3: Draw Particle Diagrams
Draw a particle diagram representing the type of matter described below each box.Your diagrams must be different from the ones provided in part 2.
|1. Mixture of elements and compounds||2. Compound|
|3. Mixture of compounds||4. Mixture of elements|
Part 4: Analysis Questions
- Check your answers for parts 2 and 3 with your teacher.Did you get any incorrect? If so, explain the mistakes you made and how you corrected them.
- Which of the diagrams in Part 2 that you identified as mixtures (labels c., d., or e.) could be classified as heterogeneous mixtures?
- Which of the diagrams in Part 2 that you identified as mixtures (labels c., d., or e.) could be classified as homogeneous mixtures?
- Choose one of those diagrams and write its number on the line: ______
- Assume that the homogenous mixtures you noted above are solutions. From the diagram you selected in 3a., draw the particles that represent the solvent and the solute:
Solvent: __________Solute: __________
- Just by looking at a sample of matter in real life (not a particle diagram), would you be able to tell the difference between a homogeneous mixture and a compound? Why or why not?
- Just by looking at a sample of matter in real life (not a particle diagram), would you be able to tell the difference between a heterogeneous mixture and an element? Why or why not?