Elements, Mixtures and Compounds
Standards VA-SOL.SC.PS.2 STANDARD: The student will investigate and understand the basic nature of matter. Key concepts include
B. elements, compounds, mixtures, acids, bases, and salts; LESSON PLAN OUTLINE
Topic Title: Elements, Mixtures, and Compounds Continued Related Concepts: • Element • Mixtures • Compounds • Organic compounds • Inorganic compounds Instructional
Objective(s) Students will define: compounds, mixtures, matter, substance, element, homogeneus, heterogeneus, colloid, suspension, and solution • Students will distinguish between compounds and mixtures • Students will distinguish between elements and compounds
• Students will describe how to determine whether a substance is an element, compound, or mixture
Materials & Resources
It's a Mixed Up World:
http://www.chemed.org/Downloads/LP_Competition/2006LessonPl ans/MixedUpWorld.pdf
Used for the graphic organizer in the Explain section and as the basis of the activity in the Expand section of this lesson
Elements, Mixtures and Compounds Beads:
http://msed.iit.edu/ids/model_lessons/chemistry/Unit_1_ElementsC ompoundBeads.doc
This lesson plan provided the basis for the activity done in the Explore section of this lesson.
Engage Students will answer the following Bellringer question:
"Besides as states of matter, are there any other ways to classify matter? If so, how? If not, why not?"
Explore Bead Sort
In this section of the lesson, students will sort beads to help them
understand the differences between elements, mixtures and compounds. Before beginning the lesson, you will need to prepare the following class set:
• For one complete sample set, fill nine petri dishes and label the lids as described in the table below.
• A Sharpie works well for the label, and a piece of clear tape over the writing will make the label more permanent.
• Use a dab of super glue to affix the lids securely.
Dish Label Dish Contents Classification
R Red beads only Pure substance,
element
B Blue beads only Pure substance,
element Gn2 Green beads, wired in pairs Pure substance,
diatomic element BGn2P Several pieces, each consisting of
one blue bead, two green beads, and a pearlwiredtogether
Pure substance, compound PGn Several pieces, each consisting of
a pearlwired toa green bead
Pure substance, compound R4Gn Several pieces, each consisting of
four red beads wired toa green bead
Pure substance, compound RGn + Gn2 Some green beads wired in
pairs, as well as several pieces consisting of a red bead wired to
a green bead
mixture
R + P + Gn2 Loose red beads, loose pearls,
and green beads wired in pairs mixture
B + R Loose red beads and loose blue beads
mixture
During the lesson, the students will be led in the following steps:
1. Divide class into pairs of students. Instruct students not to open the dishes.
2. One student from each pair should come forward to obtain a bag of samples.
3. Ask students to sort the dishes into three groups based on similarities in the contents of the dishes. Emphasize that when students disagree with their partners about the classification, they should discuss their ideas until a consensus is formed.
4. As a class, present and discuss the different ways that the students sorted the dishes. Ask the students to explain why they sorted the dishes the way they did.
Explain Students will be led in a discussion of the ideas related to elements, mixtures and compounds. As the discussion moves forward, students will be led in completing a graphic organizer (tree diagram) of the information being discussed in class. Ask students what elements, mixtures, and compounds we encounter everyday.
Key Vocabulary: • Matter • Substance • Compound • Element • Compound • Homogeneus • Heterogeneus • Colloid • Suspension • Solutions
Extend It's a Mixed Up World
MATERIALS NEEDED:
• Examples of elements (aluminum and copper), compounds (salt, water, ammonia, and sugar), and mixtures (oil and vinegar salad dressing, cake, vinegar, and glass)
• Safety Goggles
• Alum (dispense in salt shakers or with a measuring spoon) • Filter materials (gauze pads, cotton, coffee filters, fabric, cheese
cloth) • Sand
• Aquarium filter charcoal
• Styrofoam cups (for layering filter materials) • Clear cups or jars for retrieving “treated” water • Jug of water with soil/mud added
• Waste collection bucket • Any other reasonable request Preparatory Directions:
• Assemble the required materials.
• Check school policies on working with solutions to see whether safety splash goggles are required.
• Prepare “untreated” water sample (muddy water).
• Put together activity kits for each group: alum, 1 styrofoam cup, 1 clear cup, and adequate amounts of each filtering option.
• Allow 1 teaspoon of alum for 1 cup of dirt water (A 53 gm jar contains about 15 teaspoons).
• Wash aquarium charcoal to avoid increasing turbidity of filtered water.
Activity Directions:
1. Show students an example and have them identify it as an element, compound, or mixture and explain their reasoning. (Either pass
examples around the room or display where each can be clearly seen.)
2. Discuss or clarify categorization of examples if needed.
3. Discuss the water purification process. The source of drinking water for many communities is river or lake water. The untreated water contains a variety of suspended and dissolved materials.
4. Divide the class into working groups of three. Explain that they will be working together to “unmix” a mixture which will result in cleaner water.
5. Provide each group an activity kit and explain that they can construct their filter out of any materials they wish.
6. Have students discuss how mixtures can be separated into pure substances in their small groups. Students should use this information to help them separate the muddy water mixture. 7. Punch holes in the bottom of the styrofoam cups to allow water
drainage. Holes don’t need to be too large or too small – remind students to use ONLY the tip of the ink pen/pencil (not the entire object) to make many holes.
8. Once a group has the filter constructed provide them with a cup of “untreated water” and instruct them to add a small amount of alum and stir – observe and record observations. Repeat until coagulation occurs. ***SLOWLY pour the “untreated” water through their filter.*** 9. Each group should produce: their ideas about how mixtures can be
separated, how they layered their filter, and their analysis of their filter (what should they have done differently)
10.If time: have teams compare the clarity of their samples after they finish. Discuss why some samples ended up clearer than others. Discuss if this activity would be possible with compounds or elements.
Evaluate Students will write an exit pass which includes: 3 things they learned
2 things they are confused about 1 question they still have
Plans for Diversity
Students will be placed in heterogeneus groups which each have a mixed ability level of students.
Notes will be written as students write them. If necessary, students will be given a copy of the notes rather than writing them themself.
Connections This lesson directly follows the set of lessons on the states of matter. Because of this, students are able to begin to see that there are multiple ways to classify matter rather than just into 3 states of matter.
After this lesson, the students will learn another method of classifying matter, acidity.
