Chemistry of the Atmosphere

Question 1

What are the theories about Earth’s early atmosphere?

Answer 1

> there was intense volcanic activity that released gases.
nitrogen built up over time.
the atmosphere probably contained mainly carbon dioxide and no oxygen.
↳ similar to Mars and Venus today.

Question 2

How does the ocean decrease CO₂ in the atmosphere?

Answer 2

By absorbing it.

> water vapour is condensed to form oceans.
↳ CO₂ is absorbed for photosynthesis.
shells and skeletons contain carbonates from oceans.
↳ layers of sediment formed from carbonate precipitates.
carbon became locked up in rocks and fossil fuels that formed as dead organisms were compressed by layers of sediment.

Question 3

What is crude oil and natural gas formed from?

Answer 3

Compressed plankton deposits.

Question 4

What is coal formed from?

Answer 4

Compressed thick plant deposits.

Question 5

What is limestone formed from?

Answer 5

Compressed calcium carbonate deposits from shells and marine skeletons.

Question 6

What is formed from compressed plankton deposits?

Answer 6

Cruse oil and natural gas.

Question 7

What is formed from compressed thick plant deposits?

Answer 7

Coal.

Question 8

What is formed from compressed calcium carbonate deposits from shells and marine skeletons?

Answer 8

Limestone.

Question 9

What is the word equation for photosynthesis?

Answer 9

Carbon dioxide + water ⟶light⟶ glucose + oxygen.

Question 10

What is the symbol equation for photosynthesis?

Answer 10

6CO₂ + 6H₂O ⟶light⟶ C₆H₁₂O₆ + 6O₂

Question 11

The increase in atmospheric oxygen led to…

Answer 11

…the evolution of animals.

Question 12

What led to the evolution of animals?

Answer 12

The increase in atmospheric oxygen.

Question 13

What are the greenhouse gases?

Answer 13

> carbon dioxide (CO₂)
methane (CH₄)
water vapour (H₂O)

Question 14

What is the greenhouse effect?

Answer 14

When greenhouse gases in the atmosphere absorb long wavelength radiation and re-radiate it in all directions, including back towards Earth, helping to keep the Earth warm.

Question 15

What are some human activities that promote climate change?

Answer 15

> deforestation.
   ↳ less carbon dioxide is removed by photosynthesis.
> burning fossil fuels.
   ↳ releases carbon dioxide.
> farm animals.
   ↳ produce methane.
> decomposition.
   ↳ landfill and agricultural waste releases carbon dioxide and methane.

Question 16

What are four possible consequences of climate change?

Answer 16

> flooding and erosion in coastal areas due to the melting of the polar ice caps causing sea levels to rise.
more frequent and severe storms.
difficulty producing food in certain areas if temperatures and rainfall patterns change.
changes in the distribution of some wild species if habitats change.

Question 17

What forms carbon monoxide and what are it’s effects?

Answer 17

FORMATION ⟶ incomplete combustion of fossil fuels.
EFFECTS ⟶ stops blood from transporting enough
oxygen around the body.
↳ can cause fainting, coma or death.

Question 18

What forms carbon particulates (soot) and what are it’s effects?

Answer 18

FORMATION ⟶ incomplete combustion of fossil fuels.

EFFECTS ⟶ respiratory problems and global dimming.

Question 19

What forms sulfur dioxide and what are it’s effects?

Answer 19

FORMATION ⟶ oxidation of sulphur impurities in fossil fuels during combustion.
EFFECTS ⟶ acid rain and respiratory problems.

Question 20

What forms oxides of nitrogen and what are it’s effects?

Answer 20

FORMATION ⟶ reaction between nitrogen and oxygen in the air caused by the heat of burning fuels such as in car engines.
EFFECTS ⟶ acid rain and respiratory problems.