The Earth's early atmosphere was similar to the atmosphere of Venus today. The main gas forming this atmosphere was:
Most of the gas which formed this early atmosphere came from:
The other gases making up this early atmosphere were:
Match the letter to the number

| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
C | arrow_right_alt | 1 |
D | arrow_right_alt | 4 |
A | arrow_right_alt | 3 |
B | arrow_right_alt | 2 |
Which gas makes up 21%

Volcanic activity

Create a time line for the evolution of the atmosphere giving the events and the changes in composition.
Atmosphere timeline
The pre-industrial modern atmosphere occurs then burning of fossil fuels increases carbon dioxide levels.
Green plants evolve and photosynthesise Carbon dioxide levels decrease and oxygen levels increase.
The earth cools and water condenses to form the oceans so CO2 dissolves in the oceans.
Volcanoes release CO2, water vapour and ammonia to form the early atmosphere.
Years ago carbon dioxide got ‘locked up’ in rock which had formed
from the remains of shellfish.
The carbon dioxide also reacted with sea water to produce insoluble
carbonates which formed as well as soluble magnesium hydrogencarbonate and calcium hydrogencarbonate that in the oceans .
Carbon dioxide was taken in during in green pants ended up as the carbon in fuels.
fossil
limestone
photosynthesis
sediment
NOW
Animals and humans produce carbon dioxide through
Plants help in removing carbon dioxide through .
This process isn’t enough to balance the extra carbon dioxide produced by the
burning of fuels.
The extra carbon dioxide contributes to global as a gas.
fossil
photosynthesis
warming
greenhouse
respiration
The early atmosphere was made up of mainly carbon dioxide, water vapour and small amounts of methane, ammonia and nitrogen, released by volcanic .
There was little or no oxygen around at this time. The early Earth was very hot, but as it cooled the water vapour in the atmosphere and formed the oceans.
As the oceans formed, carbon dioxide in the ocean.
The carbon dioxide formed carbonates and out (formed solids).
This process reduced the amount of carbon dioxide in the atmosphere.
Approximately 2.7 billion years ago, plants and algae evolved. This decreased the amount of carbon dioxide in the atmosphere and increased the amount of oxygen in the atmosphere due to .
When sea animals evolved they used the carbon dioxide in the ocean to form their shells and bones (which are made of carbonates). When these sea creatures died their shells and bones became (calcium carbonate), which is a sedimentary rock.
Once enough oxygen was in the atmosphere, it could support animals, which carry out . These processes have caused the levels of gases in the atmosphere to be where they are today.
6 mark question to use to make a model answer.
oxygen has overall
carbon dioxide has overall
water vapour has overall
carbon dioxide small over last 500 years
carbon dioxide decreased due to
oxygen increased due to
water vapour into the oceans
carbon dioxide in the oceans
carbon dioxide formed sedimentary rocks ( )
carbon dioxide formed fuels
In the last 500 years carbon dioxide increased by human activity such as of fossil fuels and cutting down trees.
decreased
photosynthesis
increased
condensed
The composition of the Earth's atmosphere has changed since it was first formed. The most significant source of carbon dioxide in Earth's early atmosphere was:
The main reason for the increase in atmospheric oxygen was:
The amount of carbon dioxide was gradually reduced because of:
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
methane | arrow_right_alt | 3 |
ozone | arrow_right_alt | 2 |
ammonia | arrow_right_alt | 4 |
nitrogen | arrow_right_alt | 1 |
MTD. Make a model answer for this question in your books
has increased overall
decreased overall
water vapour has overall
carbon dioxide small increase over last years
Explanations
carbon dioxide decreased due to and oxygen increased due to
(carbon dioxide + water -> sugar + oxygen in the presence of light)
water vapour to form the oceans
carbon dioxide in the oceans
carbon dioxide formed rocks (limestone)
carbon dioxide formed fossil
carbon dioxide increased by activity
carbon dioxide increased from burning of fuels
Fossil fuels and carbonate rocks

Actions of plants

Which gas makes up most of the trace gasses

Which gas makes up most 0.03% of the air

The gases in the early atmosphere were caused by ___________________ eruptions
Which two planets the solar system have atmospheres that are similar to the early earth atmosphere?
The Earth’s early atmosphere was thought to contain
Which gas condensed to form the oceans as the crust cooled
Which of the following caused the concentration of carbon dioxide in the atmosphere to decrease
The growth of primitive plants used carbon dioxide and released oxygen by __________________ and consequently the amount of oxygen in the atmosphere gradually increased
As the amount of fossil fuels that have been used increased the percentage of CO₂ in the atmosphere has
Change in atmosphere
When plants developed and photosynthesised was removed. Photosynthesis produces O2 which caused levels in the air to rise so the proportion of to decrease.
dissolved in oceans and formed sedimentary rocks.
Formation of fossil fuels trapped
fell to 0.03%
Respiration and photosynthesis balanced in air
humans burned fossil fuels
fossil fuels produce when burned
has risen to 0.04% due to human activity
Note the volume of gas has decreased by 21%

To confirm that a gas is oxygen
To confirm that a gas is hydrogen
To confirm that a gas is carbon dioxide
To confirm that a gas is chlorine
To confirm that a gas is ammonia
Gas question

What is the definition of global warming

and other short wave radiation passes in through the atmosphere and is absorbed by the earth.
As the earths surface is hotter radiation is radiated outwards.
Some of the radiation is trapped by gases in the atmosphere.
This causes global which leads to change.

The greenhouse effect

The radiation that passes through the atmosphere is in the _ _ part of the spectrum
The radiation that is reflected by the atmosphere back to earth is in the _ _ part of the spectrum (called thermal radiation in chemistry)
Short wavelength radiation from the Sun passes through the atmosphere
This causes global warming (an increase in the global average temperature).
The lower energy radiation is reflected back (now long wavelength)
The radiation hits the Earth's surface, where some of its energy is absorbed (warming the Earth)
Greenhouse gases in the atmosphere absorb this long wavelength radiation (warming the Earth)
Which of the following are greenhouse gases?
As the amount the percentage of CO₂ in the atmosphere has increased the average global temperature
Deforestation has caused CO₂ levels to
Planting more trees will cause CO₂ levels to
Increased production of methane due to livestock farming will cause global warming to
Increased production of CO₂ burning more fossil fuels will cause global warming to
Which of the following are effects of climate change due to global warming?