Unit E: Section 1-2 Flashcards Preview

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Flashcards in Unit E: Section 1-2 Deck (65):
1

What is potable water?

Water that humans can safely drink

2

How much water on the earth is saltwater?

97%

3

How much water on earth is fresh water?

3%

4

Of all the fresh water, how much is ice?

77%

5

Of the fresh water on earth how much is ground water?

22%

6

Of the freshwater how much is in rivers, lakes, and wetlands?

1%

7

Where is the most fresh water on earth?

In is in ice form

8

What does water quality describe?

How pure water is

9

What does water get tested for?

Taste and odor
Turbidity (cloudiness) and color
Toxic substances and pollutants
Bacteria
Hardness and mineral content
Ph level of 7
Dissolved oxygen level
Suspended solids
Dissolved solids

10

What is salinity?

The total amount of saltS dissolved in water

11

What is hard water?

Hard water contains a high concentration of the minerals calcium and magnesium

12

What does hard water do?

They leave mineral deposits in appliances

13

What type of organisms can be found in freshwater?

E.coli and minerals

14

Why don't people who get water from a well need to get their water tested often?

Because it comes from deep underground and is protected from most pollutants

15

What do they do to clean water?

They filter it and treat it with chemicals

16

What can give a rotten egg smell in water?

Hydrogen sulphide

17

What are the two processes to turn saltwater to fresh water?

Distillation and reverse osmosis

18

Explain the process of distillation?

Saltwater gets heated until it evaporates. And only the water evaporates. Then as it goes down a tube it condenses and leaves pure water

19

Explain the process of reverse osmosis

It forces saltwater through a membrane that has holes not big enough for salt to pass through. So it moves from low concentration of water to high concentration

20

What kind of waves do boats create?

They create waves called wash.

21

What can was do to smaller boats?

They can sink small ones, damage moored ones and contribute to shore erosion

22

What are waves?

Changes in patterns that move along the waters surface. They make water move in a circular motion

23

What causes waves?

Wind

24

What causes the tops of waves to rise?

When waves near the shore the bottoms drag on the bottoming the ocean floor

25

What affect do waves have on a shoreline?

The forces of waves crashing against a shoreline can change the shape. But small waves move more gently and deposit sediments

26

What is tide?

The gradual change in water height

27

What is high tide?

The highest water level along a shoreline

28

What is low tide?

The lowest water level on the coast

29

What causes tides?

Tides are caused by the gravitational force of the moon. As the moon orbits the earth it pulls water with it

30

What are stream characteristics?

Things that describe a stream

31

What do stream characteristics describe?

The rate of water flow and the slope of the streams bed

32

How do hot springs deposit sediments?

They bring water from deep underground. And because it was from deep underground it is at a higher temperature and that means it can hold more dissolved solids. But as it comes up the earth then it cools down and can hold less minerals

33

How does a stream or river start?

A glacier melts and the water collects until it starts a small stream. And then other streams join together to make a river

34

How does a river flow in the early stage?

It flows swiftly and fairly straight

35

What happens when a river reaches lower levels?

It flows slower and theta causes it to move on big curves called meanders. The flat land on wait her side gets covered with water when it overflows. That area is called a flood plain.

36

What is a meander?

Wide curves that a river bed does when it reaches ground level.

37

What is a flood plain?

A flood plain is the area that water overflows onto when it slows down

38

What happens when a river reaches the ocean?

It slows down much more and it drops its sediment load in triangle shapes called a delta

39

What can cause erosion?

Chemical weathering

40

What causes caves?

Caves are caused when rivers or streams break down big rocks like limestone

41

What is watershed?

Watershed is all the area of land that drains into one main lake or river

42

What determines the direction of watershed?

The continental divide?

43

What is the continental divide?

The highest land in a continent

44

What is the continental divide in North America?

The Rocky Mountains

45

Where does water flow if it is to the west of the continental divide?

The Pacific Ocean

46

Where does water flow of it is to the east of the continental divide?

To the Arctic or the Atlantic Ocean

47

What are continental shelves?

Shallow edges around the edges of continents. Mainly made of sedimentary deposits.

48

Where are continental shelves largest?

On the edge of Oceans that are opening up

49

How do trenches form?

Trenches form when plates are moving toward each other. The thinner oceanic plate is pushed below the thicker plate

50

What are seamounts?

Under water volcanoes that don't reach the ocean surface

51

What are mid-ocean ridges?

When molten rock pushes up from the interior of the earth. The two plates beside it are moving away from each other

52

What happens when plates move toward each other?

Trenches form

53

What happens when plates move away from each other?

Ridges and faults form

54

What are glaciers?

Large moving bodies of ice

55

What are glaciers that cover vast bodies of land called?

Continental glaciers

56

How do glaciers grind down and shape the land they pass over?

As they move pieces of rock become embedded in them. It is these pieces of rock combined with he massive glaciers that shape the land it passes over

57

What are moraines?

Rocks that form at the edge of glaciers as they mele

58

What are eskers?

Eskers form when part of a glacier melts. They form when the water flow under the glacier in tunnels. The melting releases sand and gravel from the glacier. And the sediments are deposited in a river type shape

59

What are drumlins?

Small hills with a teardrop shape. They form when a glacier moves over a moraine.

60

What is climate?

The average weather measured over a long period of time

61

How do large bodies of water affect climate?

Because they are able to hold heat for a long time for the the temperature to change. Therefore it takes a they prevent extreme temperatures

62

What is a chinook?

A chinook is when warm moist air from the ocean travels to the top of a mountain and loses some of it moisture then goes back down a mountain in warm dry winds called a chinook

63

What are currents?

Streams of water that move within a larger body of water

64

What causes currents?

Wind
Temperature differences in water
Salinity differences
Earths rotation

65

How are currents different from waves?

Currents actually move from place to place