50
Check yourself: Earth’s riches
Textbook: Part 2, pp. 74–75
GoalReview the unit “Riches of the Earth”: soil, minerals, fuels, metals, building materials and saving them.
New words
soil · tuproqore · rudaalloy · qotishmarecycling · qayta ishlash
Explanation
Review. Soil is a fertile layer of sand, clay, humus, salts, water and air. Minerals form three groups: fuels (coal, oil, gas), ores (which give metals) and non-ore (sand, salt, marble, clay). They are dug openly in a quarry or underground in a shaft. Metals are ferrous (iron, steel) or non-ferrous (copper, aluminium, gold); an alloy is a mixed metal. Fuels and metals are non-renewable, while wind and solar energy are renewable. Builders use granite, marble, sand, brick and cement. Saving, recycling and mending are a job for all of us.
Worked examples
Ore → metal → object → recycling → metal again.
Class activity
Game: write 10 cards (coal, sand, copper, marble, oil, salt, iron, gas, clay, gold) and sort them into “fuel”, “ore” and “non-ore” groups.
Practice
1
What is soil made of?
Sand, clay, humus, mineral salts, water and air.
2
Which minerals are fuels?
Coal, oil and natural gas.
3
How do we protect natural riches?
Save, recycle and mend.