Year 7: Chemical World-­‐ Mixtures Check Date Revise assumed knowledge: ST3-­‐12MW identifies the observable properties of solids, liquids and gases, and that changes made to materials are reversible or irreversible □ ST3-­‐13MW describes how the properties of materials determine their use for specific purposes CW3 Mixtures, including solutions, contain a combination of pure substances that can be separated using a range of techniques. (ACSSU113) TYPES OF MIXTURES 4CW3a. describe the importance of water as a solvent in daily life, industries and the environment 4CW3b. describe aqueous mixtures in terms of solute, solvent and solution Literacy activity (ESL focus): Define and describe. □ matter, atoms, pure, elements, compounds, mixtures, aqueous, solvent, solute and solution Recall basic description of matter, atoms, elements, compounds and mixtures Construct a table of pure and impure substances Describe the features of different types of mixtures providing examples of each • Solution • Suspension • Colloids • Emulsion First-­‐hand investigation: Solutions-­‐ Salt water or sugar in water (Oxford p180). Weigh beaker and 100mL water. Add 3 teaspoons of salt OR sugar. Dissolve. Evaporate water off. Weigh again. Compare pre and post weights. Discuss in terms of mixture, solvent, solute and solution Describe solutions in terms of concentration, dilute and saturated First-­‐hand investigation: Comparing the amount of solute in 100mL of diet v’s normal coke. Weigh and then evaporate the solvent off. Compare weights after First-­‐hand investigation: Emulsion and emulsifier-­‐ Mixing olive oil and water (Oxford p182). First-­‐hand investigation: Students are to design a task that investigates the rate (speed) of a solute dissolving and/or the amount of solute that will dissolve. Materials provided could include salt, sugar, copper sulfate (Oxford p183) First-­‐hand investigation: Students are to design a task that investigates water as a solvent. Materials provided could include copper carbonate powder, bath salts, talcum powder, flour, cooking salt and brown sugar (Oxford p184) Describe the importance of water as a solvent in • daily life, • industries and • the environment Extension: Research task or teacher delivered. Describe how desalination and water recycling function in terms of concepts covered in this topic. □ □ □ □ □ □ □ □ □ □ □ First-­‐hand investigation: Salt or fresh water (Oxford p185). Conduct series of experiments to determine if solution C is salt water or freshwater by comparing □ results of tests to solutions B and C. Assessment: Oxford online test-­‐ Types of mixtures □ Students to achieve 100% in Support and Consolidate OR Consolidate and Extend SEPARATING MIXTURES 4CW3c. relate a range of techniques used to separate the components of some common mixtures to the physical principles involved in each process, including filtration, decantation, evaporation, crystallisation, chromatography and distillation 4CW3d. investigate the application of a physical separation technique used in everyday situations or industrial processes, eg water filtering, sorting waste materials, extracting pigments or oils from plants, separating blood products or cleaning up oil spills 4CW3e. research how people in different occupations use understanding and skills from across the disciplines of Science in carrying out separation techniques Research task or teacher delivered: Construct a table of common daily mixtures and list the ingredients in each. • food mixtures □ • pharmacy mixtures • mixtures for machines Research task or teacher delivered: □ List three professions that involve making mixtures. Research task or teacher delivered: Construct a table that lists 5 mixtures you use every day and 5 pure substances. □ Answer questions Oxford p190. Recall the difference between physical and chemical properties of a substance Literacy activity (ESL focus): Define and describe. Sedimentation, flotation and decantation, centrifuging, magnetic separation, filtration, evaporation and crystallisation and distillation Research task or teacher delivered: Construct a table of the above separation techniques. Include • How it separates • description of method • diagram of equipment • two mixtures that the technique separates • a profession that uses the technique First-­‐hand investigation: Separation challenge (Oxford p191) Pan, design and perform an experiment that separates a mixture of sand, iron filings, sawdust and salt. First-­‐hand investigation: Cleaning dirty water using flocculation (Oxford p193). Half fill two 500mL beakers with muddy water. To one add half test-­‐tube of aluminium sulfate solution. To the other SLOWLY add half test-­‐tube of sodium carbonate solution. Leave for 15min. Record observations. Extension-­‐ Research task or teacher delivered: • Research current technologies used to separate blood products. Evaluate the development of artificial blood • Research current technologies used to clean oil spills. Evaluate the impact of oil spills v's the usage of oil □ □ □ □ □ □ Research current technologies used to produce our water supply and clean sewage. Evaluate the impact of the new desalination plant in Sydney Literacy: COSMOS. Students research for a related article. Students then write a series of □ questions that MUST include 5 multiple choice, 2 identify, 2 describe, 1 explain and either 1 assess or evaluate. Assessment: Oxford online test-­‐ Separating Mixtures □ Students to achieve 100% in Support and Consolidate OR Consolidate and Extend SEPARATING SOLUTIONS 4CW3c. relate a range of techniques used to separate the components of some common mixtures to the physical principles involved in each process, including filtration, decantation, evaporation, crystallisation, chromatography and distillation 4CW3d. investigate the application of a physical separation technique used in everyday situations or industrial processes, eg water filtering, sorting waste materials, extracting pigments or oils from plants, separating blood products or cleaning up oil spills 4CW3e. research how people in different occupations use understanding and skills from across the disciplines of Science in carrying out separation techniques •
Recall the definition of evaporation and crystallisation □ First-­‐hand investigation: Separating salt by evaporation and crystallisation (Oxford p204). Teacher to prepare saturated solution of salt water prior to lesson. □ Students to obtain salt crystals in watchglass. First-­‐hand investigation: Growing crystals (Oxford p204). Students to produce a super saturated solution of either Potassium Aluminium □ Sulfate (potash) or Copper Sulfate. Following instructions grow crystals on cotton wool. Literacy activity (ESL focus): Define and describe. □ Distillation, condensation and chromatography Describe applications of distillation in real world applications • Whisky production □ • Fractional distillation of crude oil First-­‐hand investigation: Chromatography-­‐ who wrote the nasty note? (Oxford □ p209). Extension-­‐ Research task or teacher delivered: Sustainable water use at home. • How do rainwater tanks collect and purify water for use on the garden and in the home • Investigate how water-­‐saving devices such as shower heads are able to reduce water loss □ • Find out more about grey water systems. Investigate: -­‐ What is grey water -­‐ What water from the home can be re-­‐used -­‐ How grey water is purified • Investigate how plants can be used as filters Assessment: Oxford online test-­‐ Separating solutions □ Students to achieve 100% in Support and Consolidate OR Consolidate and Extend 4CWadd5 investigate how the chemical properties of a substance will affect its use, eg flammability and ability to corrode Research task(s) • investigate how the chemical properties of a substance will affect its use, eg flammability and ability to corrode – Fire brigade uniform – Swimsuits – Bridge construction – Car racing gear □