Structure of the earth + the atmosphere

Question 1

What is the earth’s crust?

Answer 1

• The outer layer of the Earth on top of the mantle.
• It is solid, relatively thin and rocky.

6 km beneath oceans
35 km beneath land

Question 2

What is the earth’s mantle?

Answer 2

A zone of hot rock in the interior of the earth located between the outer crust and the molten core. It has the properties of a solid, although it can also flow, very slowly.

It is approx 3,000 km deep

Question 3

What is the earth’s core?

Answer 3

• The core is the innermost part of the Earth.
• It is made of nickel and iron.
• The outer core is hot liquid iron and is approximately 2,000 km deep
• The inner core is solid iron and nickel alloy and is approximately 1,000 km deep

Question 4

What is the atmosphere?

Answer 4

The layers of gases that surround the Earth. The important gases in the atmosphere are nitrogen, oxygen and carbon dioxide.

Most of the atmosphere lies within 10 km of the earth’s surface. The rest is within 100 km but it’s hard to judge.

Question 5

What are the main gasses in air? And what are their percentages?

Answer 5

78% = nitrogen (N2)
21% = oxygen (O2)
1% = other gasses of which 0.9% is argon (Ar)

Question 6

What happens to oxygen the higher you go?

Answer 6

The oxygen becomes less the higher you go.

Question 7

How much water is present in the air?

Answer 7

The amount of water in the air varies depending on the weather.

Question 8

Which gas is present in the atmosphere that is needed by all animals in order to survive?

Answer 8

Oxygen is needed by all animals in order for them to survive.