Extracting Lead from Lead Oxide - BBC

Curriculum and learning links: ... Ask students to observe how this affects its flexibility and link this to the way that ... Add a thin layer of copper oxide powder. 4.
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Metals: extraction, reactivity, properties and alloys

Zinc

Silver cutlery

Old Iron

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Metals: extraction, reactivity, properties and alloys Suitable for: 14 –16 years Curriculum and learning links: Reactivity series, extraction of metals, alloys, properties of materials Learning objectives: • Describe how different metals can be extracted using ideas about their reactivity. • Explain how an alloy’s properties can be different from its constituent elements.

Activities: Opening activity • Split the class into two halves. Give each group a set of Element Cards and challenge the students to see which group can arrange themselves into the correct order of reactivity first. Extracting Metals • Give students one of the Extracting Copper or Extracting Lead worksheets and ask them to either extract copper from copper oxide or lead from lead oxide using the method on the worksheet. • Watch Clip 31 to find out more about metal extraction. Changing Properties • Ask students to investigate how combining substances can change their properties by adding small amounts of sand to plasticine. • Ask students to observe how this affects its flexibility and link this to the way that adding carbon to iron to make steel makes it stiffer and stronger. • Watch Clip 32 and then demonstrate one or more smart metals.

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Metals: extraction, reactivity, properties and alloys

Reflect and review • Ask students to review the knowledge that they have acquired and the skills that they have developed during this lesson. How might they link this to their everyday life?

Want to explore further? • You could challenge students to research the uses of smart metals and other smart materials. Inspired by their research, they could ‘design’ a smart material and describe what it could be used for as a result of its properties. Students could summarise this in a Bang Goes the Theory poster using the template provided on page 62, or by doing a presentation to the class. Possible prompts for their poster or presentation might include: Name of smart material: What is it made from? Unusual properties: Possible uses (remember to explain each one using ideas about properties):

You will need • Clip 31 (5’37”) • Clip 32 (2’10”) • Two sets of Element Cards • Extracting Copper from Copper Oxide worksheet Or: Extracting Lead from Lead Oxide worksheet • Bang Goes the Theory poster template • Carbon powder • Copper oxide Or: Lead oxide

• Small tin lids or metal bottle tops • Plasticine • Sand • Smart metal alloys – for example a two-way memory spring (available online) • Bunsen burners • Tongs • Heatproof mats • Spatulas • Beakers • Tap water

Technician’s notes: • Metal bottle tops provide a very good way of heating small quantities of powders, but the rubber seals will need to be removed first. Any residue can be burned off using a hot Bunsen flame. • Extracting copper requires a very high temperature. It might be helpful if the teacher circulates with a butane-powered Brulée torch in addition to the students heating strongly with a Bunsen burner.

Health and safety: tection). ly for all activities (including eye pro • Normal laboratory guidelines app mful. See CLEAPSS Hazcards for har is de oxi per cop and ic tox is de • Lead oxi further information. r to ensure that an adequate risk • It is the responsibility of the teache assessment has been completed. © BBC

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Element Cards

Calcium