Structure and Composition of Earth's Atmosphere

Which of the following gases is the most abundant in Earth's Troposphere?

• Nitrogen (N2)
• Oxygen (O2)
• Argon (Ar)
• Carbon Dioxide (CO2)

What is the percent of oxygen within the Earth's Troposphere?

• 78%
• 21%
• 1%
• none of these

What is an example of a trace gas within the Earth's Atmosphere?

• Oxygen
• Nitrogen
• Carbon Dioxide
• Neon

As you increase the altitude in the atmosphere, air pressure and density

• increase, this is due to the surface area of the atmosphere increasing with increasing altitude.
• decrease, the is due to the surface area of the atmosphere increasing with increasing altitude.
• remain the same.
• there is no change within the air pressure and density as you increase the altitude within the atmosphere.

What is the first layer within the Earth's atmosphere (aka. the layer closest to Earth)?

• Troposphere
• Stratosphere
• Mesosphere
• Thermosphere

As you increase altitude within the troposphere, temperature

• increases, this is due to that the Earth radiates the heat back to space
• decreases, this is due to that the Earth radiates the heat back towards space
• stays the same
• does not change

Which of the following is one of the phenomena found within the troposphere?

• burning meteors, this is due to the molecular structure of the troposphere
• The ozone layer, which is responsible for the absorption of ultra-violet radiation.
• Weather, this is due to the decreasing temperatures with increasing altitude in the troposphere.
• Satellites are found within the troposphere.

The layer above the troposphere is called?

• Mesosphere
• Thermosphere
• Troposphere
• Stratosphere

The stratosphere is important because

• it has an ozone layer, within which it protects life from infrared radiation which would otherwise cause us to burn.
• it has an ozone layer, within which it protects life from ultra-violet radiation which would otherwise cause us to burn.
• it burns up meteors.
• contains the aurora borealis.

As the altitude increases in the stratosphere, temperature tends to

• decrease
• increase
• stay the same
• none of these