CHAPTER 10. THE ATMOSPHERE 10.3
- The atmosphere is arelatively thin layer ofgases which support life and provide
protection to living organisms. The force of gravity holds the atmosphere against the
Earth. The diagram below shows the temperatures associated with the various layers
that make up the atmosphere and the altitude (height) from the Earth’s surface.
0
10
20
30
40
50
60
70
80
90
100
110
120
-100-90 -80 -70 -60 -50 -40 -30 -20-10 0 10 20
Height (km)
Temperature (◦C)
A
B
C
D
(a) Write down the names of the layers A, B andD of the atmosphere.
(b) In which one of thelayers of the atmosphereis ozone found?
(c) Give an explanationfor the decrease in temperature as altitude increases in layer
A.
(d) In layer B, there isa steady increase in temperature as the altitudeincreases.
Write down an explanation for this trend.
- Planet Earth in Danger
It is now accepted thatgreenhouse gases are toblame for Planet Earth get-
ting warmer. The increase in the number of sudden floods in Asia and
droughts in Africa; the rising sea level and increasing average temperatures
are global concerns. Without natural greenhouse gases,like carbon dioxide
and water vapour,life on Earth is not possible. However, the increasein
levels of carbon dioxidein the atmosphere sincethe Industrial Revolution
is of great concern. Greater disasters are to come, which will create mil-
lions of climate refugees. It is our duty to takeaction for the sake of future
generations who will pay dearly for the wait-and-see attitude of the current
generation. Urgent action to reduce waste is needed. Global warming isa
global challenge and calls for a global responsenow, not later.
(Adapted from a speechby the French President,Jacques Chirac)
(a) How do greenhousegases, such as carbon dioxide, heat up the Earth’s surface?
(b) Draw a Lewis structure for the carbon dioxide molecule
(c) The chemical bondswithin the carbon dioxide molecule are polar. Support this
statement by performinga calculation using the table of electronegativities.
(d) Classify the carbondioxide molecule as polar or non-polar. Give areason for
your answer.
