chemistry of the atmosphere

Question 1

how is methane produced?

Answer 1

-farm animals- during digestion
-waste that we prod - by decomposition

Question 2

consequences of climate change on weather

Answer 2

-rare weather events become more severe and common
-sea level rising
as water warms up it expands

Question 3

difference betw climate and weather:

Answer 3

-weather, short term atmospheric conditions

-climate, long term weather conditions in a region

Question 4

what is carbon footprint?

Answer 4

total amount of co2 or other GHG’s in somethings entire life cycle

Question 5

benefit of knowing about co2 emission of things?

Answer 5

-know how damaging they are (worth the cost?)
-know what is most polluting, try reducing

Question 6

When burning fossil fuels, how is sulfur dioxide formed?

Answer 6

Sulfur is an impurity in some fossil fuels and is oxidised when they’re combusted

Question 7

how is oxides of nitrogen produced when petrol is burnt in car engines

Answer 7

-nitro from atmosphere and oxy from atmosphere react together at high temps in the car engine

Question 8

state the greenhouse gases

Answer 8

water vapor, carbon dioxide, methane

Question 9

what happened to the water vapor in early atmos?

Answer 9

-condensed to form oceans
-some of the co2 dissolved in oceans to form weak acid
-this reacted w/ minerals in sea to form precipitates
-over time, formed sediments of carbonate rock on the sea bed, trapping carbon

Question 10

what did some of the co2 in the sea make?

Answer 10

-used to make corals and shells of organisms such as mussels
-when these died, formed sedimentary rock limestone -> also removed co2 from atmosphere

Question 11

how was oxygen first introduced into the atmosphere

Answer 11

• 2.7 billion years ago
• photosynthetic algae started forming
• produced oxygen
• over the following billion years plants evolved

Question 12

state the greenhouse gasses

Answer 12

water vapor, carbon dioxide, methane

Question 13

describe the greenhouse effect in terms of radiation

Answer 13

• energy from the sun travels to the earth as shortwave radiation
• some reflected back into space, most past easily thru atmosphere, bcs short rad doesn’t interact strongly with gas molecules in atmosphere
• energy absorbed when it reaches the surface of the Earth
• the surface of the earth now radiates the energy as long wave radiation
• energy in long wavelength radiation absorbed
• because energy trapped in atmosphere, causes temp of atmosphere to increase

Question 14

greenhouse gasses absorb…

Answer 14

• long wavelength radiation, that gets reflected back off the Earth

Question 15

Describe the shape and structure of this polymer. (DNA)

Answer 15

two polymer chains
four (different) monomers / nucleotides
(double) helix

Question 16

sulfur dioxide is prod when:

Answer 16

• fuels that contain sulfur are combusted, the sulfur is oxidised

Question 17

oxides of nitrogen prod when:

Answer 17

• prod inside engines; high temps cause nitrogen and oxygen to react

Question 18

pollutants that can be formed from combustion of fuels

Answer 18

• carbon monoxide
• particulates of soot and unburnt hc’s
• sulfur dioxide
• oxides of nitrogen

Question 19

The diatomic elements are hydrogen, nitrogen, fluorine, oxygen, iodine, chlorine and bromine.

Answer 19

hydrogen, nitrogen, fluorine, oxygen, iodine, chlorine and bromine.

Question 20

how is coal formed

Answer 20

-from remains of ferns and trees
-if they die in marshy wetlands, no decomposition bcs lack of o2 or acidic conditions, bacteria cant decompose
-over time, covered w/ sediment and compressed
-high temp & pressure makes coal

Question 21

how is crude oil formed

Answer 21

-plankton die and settle in mud on sea-bed
-if no o2, no decomposition
-over time compressed into sediment
-heat and pressure convert into crude oil