Year 7 Science · Unit 2 · Lesson 6

Metals, Non-metals and Metalloids

Challenge Worksheet

Name

Date

Class

Learning Goals

Reason about consequences when a known property of an element changes.
Connect element properties to real industrial and societal impacts.
Use scientific terminology accurately in an extended response.

Go Deeper

What if…?

Scenario

Aluminium (Al) is currently the world's most widely used non-ferrous metal. It is valued because it is lightweight, malleable, ductile, a good conductor of electricity and heat, and it forms a thin oxide layer that protects it from further corrosion. Australia is one of the world's largest producers of bauxite (aluminium ore), mined at Weipa in Queensland and the Darling Range in Western Australia.

Now imagine that, overnight, aluminium became as chemically reactive as sodium. Sodium (Na), also a Group 1 metal, reacts explosively with water and bursts into flames when exposed to air unless kept in oil. If aluminium had sodium's reactivity, it could no longer be safely used in aircraft, cars, building frames, power lines, food packaging or drink cans, as it would react dangerously with moisture and oxygen in the air.

Using what you know from this lesson about metal properties and their applications, predict and explain what would happen to Australian industry and everyday life if aluminium were as reactive as sodium. Name at least three specific industries or products that would be affected and explain the science behind each impact. Use scientific terms in your answer.

Challenge 4 marks

Show What You Know

1. Mercury (Hg) is a metal that is liquid at room temperature. Gallium (Ga) melts at 29.8 °C — below body temperature, so it melts in your hand. Using the lesson's description of how to classify metals, explain why both mercury and gallium are still classified as metals despite not being solid at room temperature. What properties do they still share with other metals?

Challenge 3 marks

2. Australia's Olympic Dam mine in South Australia produces copper (Cu), gold (Au) and uranium (U) — all elements. For each element, name one property from the lesson that explains why that specific element is commercially valuable. Use the terms metal/non-metal/metalloid and at least one property word (shiny, malleable, ductile, conductor, brittle, semiconductor) in your answer.

Challenge 3 marks

Wrap Up

In one sentence, what was the main idea of this lesson?