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Flashcards in Chapter 7 Energy Sources Deck (45):
1

Concentration

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

2

Gangue

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

3

Reduction

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

4

Smelting

Melting mineral ore in order to separate the metal contained

5

Purification

The removal of impurities from metals to produce a pure metal

6

Crust

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

7

Minerals

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

8

Mineral ore

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

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Mining

The process of removing mineral ore from the ground

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Open-cut mining

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

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Underground mining

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

12

Fossil fuels

Substances, 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

13

Peat

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

14

Sediment

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

15

Sedimentary rocks

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

16

Brown coal

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

17

Black coal

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

18

Overburden

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

19

Natural gas

A fossil fuel consisting of mainly methane

20

Porous

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

21

Turbines

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

22

Wind energy

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

23

Biomass

Material produced by living organisms

24

Ocean wave energy

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

25

Tidal energy

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

26

Geothermal energy

Heat energy transferred from rocks below the Earth’s surface

27

Hydro-electric

Power produced by the energy of falling water

28

Nuclear energy

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

29

Clouds

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

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Fog

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

31

Water cycle

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

32

Gyres

Permenant circulating deep ocean currents that enclose huge areas between continents

33

Greenhouse effect

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

34

Global warming

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

35

Blackwater

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

36

Greywater

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

37

Biodegradable

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

38

Desalination

The conversion of sea water to fresh water

39

Weathering

The process of breaking down rocks by conditions in the atmosphere

40

Erosion

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

41

Soil

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

42

Deposition

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

43

Humus

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

44

Deforestation

The removal of trees from the land

45

Groynes

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