Matter Changes and Mixtures

Overview

Lesson 3 of 10 in the “Manitoba Science Year Overview” unit. Students investigate how observable properties help identify materials and choose methods to separate a mixture while recognizing that matter is conserved.

Learning intentions

• Students will be able to measure and describe physical properties of materials.
• Students will be able to distinguish a mixture from a single material or solution.
• Students will be able to select a separation method based on material properties.
• Students will be able to explain that separating a mixture does not destroy matter.

Success criteria

• I can record observations and measurements using appropriate units.
• I can use properties such as magnetism, solubility, texture, and density to identify materials.
• I can explain why a chosen method separates a mixture.
• I can describe how matter is conserved during a physical change or separation.

Curriculum links

• Develop and use models to describe matter as particles too small to see.
• Plan and conduct investigations, record data, and use evidence to explain results.
• Write informative explanations using observations, measurements, and evidence.
• Represent and interpret measurement data, including mass and volume, in tables.

Lesson structure (60 minutes)

1. 0–7 minutes – Hook and prediction Open with the hook and introduction slides showing a jar containing soil, gravel, salt, and water. Ask: “If these materials are mixed, can we get them back?” Students make a quick prediction and share one property that might help. Emphasize that a mixture contains two or more materials that can often be separated physically.

2. 7–15 minutes – Review properties and particle ideas Use the properties and particle-model slides to review matter, mass, volume, density, solubility, magnetism, texture, and conductivity. Students examine the states of matter particle cards and sketch or describe how particles are arranged in solids, liquids, and gases. Clarify that dissolving changes how a material is distributed, not whether its matter exists.

3. 15–22 minutes – Model the investigation Demonstrate a small sample of the mixture: use a magnet to remove magnetic material if present, allow gravel to settle, pour through a filter, and explain how evaporation could recover dissolved salt. Model safe handling and careful observations. Ask students to predict what will happen at each stage and identify the property being used.

4. 22–43 minutes – Team separation investigation Place students in five mixed-ability teams of five. Give each team a prepared sample of soil, gravel, salt, and water, along with equipment. Distribute the mixture-separation investigation sheet. Teams plan and carry out a sequence using available methods such as sorting, magnetism, settling, filtering, and evaporation. Students record the material removed, property used, evidence observed, and any matter that remains in the equipment.

5. 43–51 minutes – Compare methods and evidence Teams display their results and explain one successful step and one limitation. Return to the investigation discussion slides and compare methods. Guide students to distinguish a physical change, such as dissolving or filtering, from a chemical change, such as rusting or burning. Reinforce that mass may appear to change if material is spilled, left in a filter, or dissolved in water, but matter has not vanished.

6. 51–57 minutes – Individual explanation Students complete the final section of the mixture-separation investigation sheet independently: “Which separation method was most useful, and why?” They must name the property involved and use one observation or measurement as evidence. Students add a simple particle-model sketch showing salt spread through water before evaporation.

7. 57–60 minutes – Exit check Use the plenary and exit-question slide. Students respond orally, on a sticky note, or by pointing/drawing: “Is filtering a physical or chemical change? How do you know?” Collect responses and note students needing reteaching.

Resources

• the matter properties and separation investigation deck
• the mixture-separation investigation sheet
• the states of matter particle cards
• Prepared mixtures of soil, gravel, salt, and water
• Clear cups or beakers, trays, spoons, and stirring rods
• Magnets in protective bags, sieves, funnels, and filter paper
• Balance, measuring cylinders, rulers, and thermometers if available
• Goggles, paper towels, waste containers, and labels
• Sticky notes or small exit slips

Assessment

• Observe teams for safe procedures, appropriate method selection, measurement, and evidence-based discussion.
• Check worksheets for accurate property tables, separation sequences, units, and particle-model sketches.
• Use exit responses to assess whether students can distinguish physical from chemical change and explain conservation of matter.

Differentiation

• Provide labeled equipment, a teacher demonstration, tactile samples, picture vocabulary, sentence frames, and a completed example for EAL learners.
• Assign team roles such as materials manager, reader, recorder, measurer, and reporter; allow drawing, oral explanation, or speech-to-text instead of extended writing.
• Offer a reduced data table, fewer measurements, calculator access, larger-print instructions, and adult support for students with learning or fine-motor needs.
• Challenge advanced students to calculate the percentage of material recovered, justify the most efficient sequence, or compare the investigation with commercial water-treatment methods.