A mixture of gases, particles, etc...

The Atmosphere

What is the atmosphere?

What is the atmosphere?

● A layer of gases that surround a planet.

What is the atmosphere made of?

Plus a lot of other
gases in very, very
small amounts

So which graph was correct?

Make a properly labeled circle graph

of our atmosphere

Plus a lot of other
gases in very, very
small amounts

Round the percentages to the nearest
0.1%

Earth's
Atmosphere

Other Gases like carbon
dioxide and argon

21 %

78%

78% of our atmosphere is
made of NITROGEN

Nitrogen, like most other gases, is invisible.

What do we use nitrogen
for?

● MOST OF THESE USES REQUIRE

NITROGEN TO BE CHEMICALLY
COMBINED WITH OTHER ELEMENTS

Oxygen = 21 % of our
atmosphere?

● Where does the oxygen in our atmosphere

come from?

● Where does the oxygen in our atmosphere come from?

● Photosynthesizing organisms!

What are some of the uses of
oxygen?

Besides breathing?

What is the third most
abundant gas (less than
1%)?

ARGON

Carbon Dioxide makes up a
very small part of our atmosphere.
0.038%

This is a good
thing.

What gases are Greenhouse gases?

Does air and the atmosphere(made
of gases) have mass and volume?

● Is it matter?

Does air and the atmosphere(made
of gases) have mass and volume?

● Is it matter?

● Yes and yes

Properties of Air

● Air has pressure

− Pressure is the force pushing on a surface or area

Properties of Air

● Air has pressure because it has weight

− The weight of all the air above exerts pressure

Crushed by air

● Imagine being at the bottom of hundreds of

blankets=you would feel the pressure

● Why aren’t we crushed by the weight of air?

Measuring Air Pressure

● Mercury Barometer-Air pressure pushes

down on the mercury in the dish, causing the
level in the tube to rise.

Measuring Air Pressure

● Aneroid Barometer-does not require a liquid

Measuring Air Pressure

HIGHER NUMBER=HIGHER AIR PRESSURE

● How is the atmosphere different from outer

space?

The atmosphere gradually thins out with increasing
altitude

● The atmosphere, when

scaled to the size of an
apple, is no thicker than
the skin on an apple.

Composition of the Atmosphere

◼ permanent gases

◼ variable gases

◼ trace gases

◼ aerosols

•

•

WATER VAPOR

Water vapor is H2O in the form of a gas. It exists in the atmosphere in varying (different) amounts ( 1-4 %).