EVM 2ND TERM

Question 1

what percentage of earth do oceans cover

Answer 1

71%

Question 2

what percentage of water do oceans and seas cover

Answer 2

97%

Question 3

fresh water covers _% of all water on earth

Answer 3

3%

Question 4

65% of this freshwater is located in

Answer 4

ice sheets

Question 5

what is precipitation

Answer 5

moisture that reaches the surface in the form of rain sleet snow or hail

Question 6

what is surface run-off

Answer 6

precipitation that flows over the ground surface eventually finding its way into streams and rivers

Question 7

define

interception

Answer 7

precipitation that doesnt reach the earths surface due to being obstructed by trees and plants

Question 8

define

infiltration

Answer 8

precipitation soaks into soils and moves into rocks through cracks and pore spaces

Question 9

define

through flow

Answer 9

downslope movement of water through the soil roughly parallel to the ground surface

Question 10

define

ground water flow

Answer 10

slow horizontal movement of water through rocks

Question 11

transpiration

Answer 11

evaporation or diffusion of water from the plant leaves

Question 12

evaporation

Answer 12

water changing into vapour in the atmosphere due to the heat

Question 13

define

condensation

Answer 13

water vapour converted back into liquid or solid particles

Question 14

surface area

Answer 14

water in lakes rivers and swamps

Question 15

ground water

Answer 15

water in the soil and in rocks under the ground

Question 16

aquifers

Answer 16

water stored in porous rocks under the ground

Question 17

Artesian aquifer

Answer 17

an aquifer in which the water is under low pressure

Question 18

Artesian Well

Answer 18

Water from a well sunk into an artesian aquifer will rise to the surface without the need for a pump

Question 19

Reservoirs

Answer 19

an artificial lake used as a source of water
supply, usually created behind a dam or by the side of a river

Question 20

Service reservoir

Answer 20

a reservoir where drinkable
water is stored e.g. Water tower and Cistern.

Question 21

define

Wells

Answer 21

a hole bored or dug into rock to reach the water stored in them

Question 22

Rivers*

Answer 22

• a large, natural stream of water flowing in a channel to the sea, a lake, or another river.
• They provide surface transfers of water to low-land areas where farms, villages, towns and cities are concentrated.

Question 23

Desalination

Answer 23

• removal of salt from seawater by distillation

Question 24

Reverse osmosis

Answer 24

pumping water at high pressure through a fine membrane

Question 24

Distillation

Answer 24

water is boiled and released as vapour, leaving salt behind

Question 25

three percent of domestic water is used for

Answer 25

drinking and cooking

Question 26

Washing and flushing the toilet takes _%

Answer 26

50%

Question 27

Washing clothes _%

Answer 27

20%

Question 28

industries use water in factories for

Answer 28

cooling mixing and making products bottling and canning food and power generation

Question 29

Agricultural uses for water

Answer 29

* Mainly for irrigation (plants need water for transporting minerals, for photosynthesis, and for the prevention of wilting): * For domestic animals.

Question 30

Water-rich countries

Answer 30

countries with plentiful fresh water supplies

Question 31

Water-poor countries

Answer 31

* countries with scarce fresh water supplies: * Dominated by desert countries

Question 32

Water conflict

Answer 32

conflict between countries, states, or groups over an access to water resources.

Question 33

Physical water scarcity

Answer 33

not enough water to meet both human demands and those of ecosystems to function effectively.

Question 34

advantages of dam projects

Answer 34

Generation of electricity in hydro-electric power plants; Flood control; Irrigation

Question 35

dams can be an alternative for

Answer 35

Alternative for burning of fossil fuels as no greenhouse gases are produced.

Question 36

Disadvantages of dam projects

Answer 36

Relocating people; Flooding land; Disrupting the life cycles of fish and other aquatic organisms

Question 37

what can dams do to resovoirs

Answer 37

Reservoir can become obstructed due to material carried into it by rivers

Question 38

Sewage

Answer 38

waste matter such as faeces or dirty water from homes and factories, which flows away through sewer

Question 39

what can Domestic waste do to water

Answer 39

pollute the water, toxify the water and cause diseases

Question 40

what Industrial processes can cause water pollution

Answer 40

use of chemicals, the processing of metal ores, and taking metals from waste heaps

Question 40

what is the Primary treatment for sludge

Answer 40

sludge digester.

Question 41

Sludge digester does what

Answer 41

grows bacteria which can break down the sludge, releasing methane which can be burnt

Question 42

what does Tertiary treatment do

Answer 42

removes stubborn contaminants that secondary treatment was not able to clean up.

Question 43

Coagulation

Answer 43

a liquid changing to a solid or semi-solid state

Question 43

# define Water treatment

Answer 43

Water is made drinkable by undergoing coagulation

Question 44

Water-borne disease

Answer 44

a disease that exists in water

Question 45

Cholera

Answer 45

intestinal infection that causes severe diarrhoea that may lead to dehydration and eventually death

Question 46

Malaria

Answer 46

a life threatening disease which is transmitted through the bite of an infected mosquito that carries a parasite. Once bitten, the parasite reaches your bloodstream.