science unit 5

Question 1

Describe how each of the following can help to identify rock. Mohs Hardness Scale: Crystal Shape: Lustre: Streak: Cleavage/fracture:

Answer 1

How hard a rock is on a scale of 1 - 10 The shape of the rock The shininess of a rock What it leaves behind when it is scratched on a scratch tile The way it broke off, jagged (fracture) & smooth (cleavage)

Question 2

Describe the three different forms of rocks

Answer 2

There is Igneous rocks, metamorphic rocks, sedimentary rocks

Question 3

Define erosion.

Answer 3

Movement of rock and mineral grains from one place to another

Question 4

What is mechanical, biological and chemical weathering?

Answer 4

mechanical weathering = physical breaking of objects
biological weathering = plants and animals breaking rocks
chemical weathering = breaking down of rocks by chemicals

Question 5

What of the four layers of Earth?

Answer 5

Crust, mantle, outer core, inner core.

Question 6

What evidence did Alfred Wegener use to create his theory of continental drift?

Answer 6

different types of organisms on different continents

Question 7

Describe the Theory of Plate Tectonics?

Answer 7

They are moving due to convection currents, and continents lay on top of them

Question 8

Describe each of the following:
Primary waves:
Secondary waves:
Surface waves:
Epicentre:
Focus:

Answer 8

Fastest, can go through solids, liquids & gas,
Slower than p waves, can only go through solids

Slowest, most destructive
Above the surface, and the surface come from this
Source of the earthquake, s & p waves start here

Question 9

How do Earthquakes relate to Tsunamis?

Answer 9

Tsunamis are created by underwater earthquakes

Question 10

How are volcanoes formed?

Answer 10

A hotspot of magma which then rises on the surface

Question 11

What is the Ring of Fire?

Answer 11

Hotspot of volcanoes and earthquakes

Question 12

Define fossil. Why are fossils useful?

Answer 12

Made out of plants and animal remains that decomposed millions of years ago, They can be converted into fossil fuels which can be used for creating electricity, starting cars and more.

Question 13

Define:
Carbonaceous Film:
Trace Fossils:

Answer 13

Fossils forming a thin residue in a rock

Evidence of animal activity

Question 14

What is the Principle of Superposition?

Answer 14

Young = top, old = bottom

Question 15

What is relative dating, radiometric dating and radiocarbon dating?

Answer 15

Relative: using fossils and the layer in which they’re found in to determine the age

Radiometric: measuring the amount of radioactive particles are in the fossil to find out the age

Radiocarbon: measuring the relative carbon in the remains of the fossil to find out the age

Question 16

What is the difference between petroleum and bitumen?

Answer 16

Petroleum is more liquid and bitumen is more solid