Science: Earth And Its Atmosphere

Question 1

How much oxygen is there in our atmosphere?

Answer 1

21%

Question 2

How much argon is there in our atmosphere?

Answer 2

0.9%

Question 3

How much nitrogen in there in our atmosphere?

Answer 3

78%

Question 4

Explain sedimentation:

Answer 4

Erosion breaks up rocks.Rivers/streams carry the tiny rock precise down to the sea. They bask against each other on the way and get smoother. They all build up at the bottom of the sea, and pressure sticks the sediments together. The new rock that is formed is a sedimentary rock- eg:sandstone.

Question 5

Explain how igneous rocks are formed:

Answer 5

They are formed when magma or lava cools. If it takes longer to cool it will have bigger crystals. An example is granite.

Question 6

How are metamorphic rocks formed?

Answer 6

Plate movements a can put some rocks under serious heat and pressure. This can cause the rock to change form. When limestone is put under all this pressure and heat it becomes marble.

Question 7

What are green house gases?

Answer 7

Green house gases are the gasses that help keep the earth warm.

Question 8

How do people increase the greenhouse gases?

Answer 8

Let out carbon dioxide from cars, let out methane gases and cut down plants/trees.

Question 9

What is made when three oxygen atoms form together?

Answer 9

An ozone.

Question 10

What is an ozone?

Answer 10

A colourless gas made from oxygen. It keeps some ultraviolet light out (less chance of getting skin cancer) but it can be dangerous to breath too much in.

Question 11

Where does lava come from?

Answer 11

The rocks under the volcanoes melt and become magma. It leave the volcano as lava.

Question 12

Name some properties of igneous rocks:

Answer 12

Hard, cannot scratch with knife.

Question 13

Name some properties of sedimentary rocks:

Answer 13

Very hard, good for building materials.

Question 14

Name some properties of metamorphic rocks:

Answer 14

Rough, hard, waterproof (porous)

Question 15

What are the main gases in our atmosphere?

Answer 15

Nitrogen,oxygen,argon.

Question 16

How was the earth formed?

Answer 16

Lots of gas and dust take floating the air. Gravity pulls it all together.

Question 17

Explain global warming:

Answer 17

Heat from the sun reaches the earth. Some heat is reflected off and some heat is generated on earth. The atmosphere then gets every very hot.

Question 18

Give a short explanation of the carbon cycle:

Answer 18

When organisms die the carbon carbon is recycled. What ever animal eats the dead animal will get some of its carbon. Every time an animal dies a tiny bit of its carbon will re-enter the atmosphere.