Chapter 7

Question 1

Crust

Answer 1

The outer layer of the Earth, including all landforms, rocks and soil

Question 2

Minerals

Answer 2

Substances that make up rocks. Each mineral has its own chemical make-up

Question 3

Mineral Ore

Answer 3

A substance that contains minerals of values, that can be obtained by mining

Question 4

Mining

Answer 4

The process of removing mineral ore from the ground

Question 5

Open-Cut Mining

Answer 5

A method of mining mineral ores that are close to the surface — a large hole is made to expose the rocks, which are then broken up using explosives

Question 6

Underground Mining

Answer 6

A method of mining mineral ores that are deep below the surface, using shafts and tunnels dug deep into the ground to access the mineral ore

Question 7

Concentration

Answer 7

The process of making a substance stronger or purer by removing or reducing the proportion of what is foreign or inessential; for example, separating mineral ore from unwanted soil, sand and other minerals

Question 8

Gangue

Answer 8

Leftover waste rock and mineral material. It is produced during the processes that extract mineral ores

Question 9

Reduction

Answer 9

Bringing a mineral ore into a metallic state by separating the non-metallic constituents

Question 10

Smelting

Answer 10

Melting mineral ore in order to separate the metal contained

Question 11

Purification

Answer 11

The removal of impurities from metals to produce a pure metal

Question 12

Fossil Fuels

Answer 12

Substance, such as coal, oil and natural gas, that has formed from the remains of ancient organisms. Coal, oil and natural gas are often used as fuels; that is, they are burnt in order to produce heat

Question 13

Peat

Answer 13

Partially decomposed plant matter, buried and compressed over millions of years by layers of other plants in marshy or damp regions

Question 14

Sediments

Answer 14

A substance deposited on land or in rivers, lakes or oceans

Question 15

Sedimentary Rocks

Answer 15

Rocks formed from sediments deposited by water, wind or ice. The sediments are cemented together in layers, under pressure.

Question 16

Brown Coal

Answer 16

A form of coal formed from peat compressed over millions of years, with much of the moisture driven out by the weight and heat of the layers above; also known as lignite

Question 17

Black Coal

Answer 17

A harder, drier form of coal than brown coal, formed from peat compressed over millions of years, with most of the moisture driven out by the weight and heat of the layers above; also known as anthracite

Question 18

Overburden

Answer 18

Rock, soil and vegetation, which are removed before mining can commence

Question 19

Oil

Answer 19

A viscous liquid derived from petroleum, especially for use as a fuel or lubricant.

Question 20

Natural Gas

Answer 20

A fossil fuel consisting of mainly methane

Question 21

Porous

Answer 21

Having many pores or other small spaces that can hold a gas or liquid or allow it to pass through

Question 22

Turbines

Answer 22

Wheels that, when turned, drive electrical generators. Steam or water are often used to turn turbines.

Question 23

Wind Energy

Answer 23

A renewable energy derived from the wind (caused by uneven heating of the Earth and its oceans by the sun), for example by the use of wind turbines in a wind farm

Question 24

Biomass

Answer 24

Material produced by living organisms

Question 25

Ocean Wave Energy

Answer 25

A renewable energy created by converting the mechanical energy of ocean waves to electrical energy

Question 26

Tidal Energy

Answer 26

A renewable energy that can be harvested from the tides in the ocean through the use of large underwater turbines placed in areas of high tidal movement

Question 27

Geothermal Energy

Answer 27

Heat energy transferred from rocks below the Earth’s surface

Question 28

Hydro-Electric

Answer 28

Power produced by the energy of falling water

Question 29

Nuclear Energy

Answer 29

The energy stored at the centre of atoms, the tiny particles that make up all substances. Nuclear energy can be released from the radioactive metals uranium or plutonium and transformed into electrical energy in a nuclear power station

Question 30

Clouds

Answer 30

A visible collection of small water droplets in the air high above the ground

Question 31

Fog

Answer 31

A visible collection of small water droplets in the air at ground level

Question 32

Water Cycle

Answer 32

The constant circulation of water on Earth, as it evaporates from the sea, condenses into clouds and precipitates

Question 33

Greenhouse Effect

Answer 33

A natural effect of the Earth’s atmosphere trapping heat, which keeps the Earth’s temperature stable. The sun’s energy passes through the atmosphere and warms the Earth. Heat energy radiated from the Earth cannot pass through the atmosphere and is trapped

Question 34

Global Warming

Answer 34

The observed rise in the average near-surface temperature of the Earth

Question 35

Black Water

Answer 35

Waste water from the toilet system of a household; raw sewage

Question 36

Grey Water

Answer 36

Wastewater from the kitchen, bathroom or laundry system of a household; it can be used for watering lawns and gardens, or for other purposes, instead of being drained into the sewerage system

Question 37

Biodegradable

Answer 37

Describes a substance that breaks down or decomposes easily in the environment

Question 38

Desalination

Answer 38

The conversion of sea water to fresh water

Question 39

Weathering

Answer 39

The process of breaking down rocks by conditions in the atmosphere

Question 40

Erosion

Answer 40

The process of moving weathered rock or soil from one place to another

Question 41

Soil

Answer 41

A complex mixture of the products of weathering and organic matter, both living and dead

Question 42

Deposition

Answer 42

The laying down of weathered rock particles and soil by rivers, wind, oceans and glaciers

Question 43

Humus

Answer 43

Organic matter resulting from the decomposition of plant and animal tissue in the soil. Humus helps the soil hold water and mineral nutrients needed by plants

Question 44

Deforestation

Answer 44

The removal of trees from the land

Question 45

Groynes

Answer 45

A jetty built into the sea to prevent the erosion of the beach

Question 46

Acid Rain

Answer 46

Rainwater, snow or fog that contains dissolved chemicals, such as carbon dioxide, that make it acidic. Acid rain can cause rock to weather faster than pure rain can.