Chemistry of the Environment

Aquifers

Plastic bottles

Cooling towers

Drainage pipes

It is pure water

It contains dissolved impurities

It is distilled water

It is under very low pressure

Evaporation

Condensation

Precipitation

Transpiration

Nitrates

Phosphates

Hydrocarbons

Lead

Hydrogen (anode) and Oxygen (cathode)

Oxygen (anode) and Hydrogen (cathode)

Chlorine (anode) and Hydrogen (cathode)

Oxygen (anode) and Sodium (cathode)

Nitrogen

Oxygen

Ammonia

Hydrogen

Water that is trapped between sand particles in a filter

Water molecules that are part of the crystal structure of a salt

Water that has been frozen into ice crystals

Water that is found in the atmosphere as clouds

Nitrification

Denitrification

Nitrogen fixation

Ammonification

Water molecules form a hydrogen-bonded 'cage' that traps small gas molecules like methane.

It is a form of ice where the oxygen atoms are arranged in a hexagonal lattice with no hydrogen bonds.

It is a complex where water molecules act as ligands to a central transition metal ion in the sediment.

It is a polymer of water molecules linked by covalent bonds rather than hydrogen bonds.

Water below the water table has had more time to react with limestone, leading to higher concentrations of $Ca^{2+}$ and $HCO_{3}^{-}$ ions.

Water below the water table is generally softer because the pressure precipitates out the dissolved minerals.

The water table level does not affect the mineral content; it only determines the total volume of water available.

Water above the water table (vadose zone) is more alkaline because it is closer to the atmospheric $CO_{2}$.

Methane

Nitrogen oxides

Argon

Carbon monoxide

Exactly 7.0

Slightly acidic (about 5.6)

Very alkaline (about 10.0)

Extremely acidic (about 1.0)

Nitrogen

Argon

Methane

Oxygen

Color

Density

Boiling point

Solubility

Trees release large amounts of methane when they grow

Trees remove carbon dioxide from the air via photosynthesis

Forests reflect more sunlight than open land

Decaying wood produces oxygen which traps heat

Internal combustion engines of petrol cars

The use of fertilizers in agriculture

Coal-fired power stations

Deforestation of tropical forests

$N_2$

$O_2$

$Ar$

$CH_4$

It requires a high activation energy because of the very strong triple bond between nitrogen atoms.

It is an exothermic reaction that occurs spontaneously at room temperature in the air.

It only occurs during lightning strikes which provide the necessary oxygen.

It is the process of denitrification carried out by anaerobic bacteria.

To provide a high surface area of porous material (like alumina) to hold the precious metal catalysts.

To act as a filter that physically traps soot particles.

To react with $SO_2$ and prevent it from leaving the exhaust.

To cool the exhaust gases before they reach the catalyst.

Carbon dioxide

Methane

Sulfur dioxide (via the formation of sulfate aerosols)

Nitrous oxide

Urea

Ammonium sulfate

Ammonium chloride

Potassium nitrate

To give leaves their green color

To help in energy transfer and root development

To kill pests and insects

To keep the soil temperature constant

Nitric acid

Sulfuric acid

Phosphoric acid

Hydrochloric acid

Diammonium hydrogen phosphate

Ammonium hexaphosphate

Ammonium hydride phosphorus

Ammonium phosphorus oxide

Granules are more colorful and easier to see

Granules dissolve more slowly, providing a steadier release of nutrients

Powdered fertilizers are always explosive

Plants cannot absorb nutrients unless they are in pellet form

Ammonium nitrate

Ammonium sulfate

Urea

Potassium chloride

17 g

34 g

51 g

68 g

71 g

142 g

213 g

284 g

$N_2(g) \rightarrow 2N(adsorbed)$

$H_2(g) \rightarrow 2H(adsorbed)$

$N(adsorbed) + 3H(adsorbed) \rightarrow NH_3(g)$

$N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g)$

21.4%

24.6%

26.5%

31.0%

Carbon dioxide

Methane

Nitrogen

Water vapor

Increased volcanic activity

The Industrial Revolution and fossil fuel use

Changes in the Earth's orbit

Natural variations in plant growth

Recycling glass

Decomposition of organic matter in landfills

Burning plastic

Composting in open air

The Earth emits shorter wavelengths

The Earth emits longer wavelengths (infrared)

The wavelengths are exactly the same

The Earth emits X-rays

It causes fish to grow larger because of more dissolved $CO_2$.

It can lead to the collapse of coral reefs and populations of shell-forming plankton, which are the base of the food web.

It makes the water too salty for most marine life to survive.

It increases the rate of oxygen production by marine algae.

Electronic transitions (electrons moving between shells)

Vibrational transitions (changes in the bond lengths or angles)

Nuclear transitions (changes in the nucleus of the atoms)

Translational transitions (changes in the speed of the whole molecule)

They only trap heat and always lead to warming.

They only reflect sunlight and always lead to cooling.

They have a dual role: reflecting incoming solar radiation and trapping outgoing infrared radiation.

They have no effect on the radiation balance of the planet.

CFCs are transparent to infrared radiation but absorb UV.

CFCs have strong absorption bands in the 'Atmospheric Window', making them very effective greenhouse gases.

CFCs react with infrared radiation to produce chlorine radicals.

CFCs reflect infrared radiation back to the sun before it reaches the surface.

Nitrous oxide

Carbon dioxide

Methane

Ozone

It is a result of human industrialization since 1750.

Without it, the average surface temperature of the Earth would be approximately $-18^{\circ}C$.

It is caused entirely by the thinning of the ozone layer.

It only involves the reflection of UV light by nitrogen gas.