Chemistry Topic 9&10 The Earth’s Atmosphere, Resources

What formed the oceans?

Water vapour condensing

Where did most Carbon dioxide go?

Oceans

What absorbs lots of carbon dioxide?

Algae

What compressed to form sedimentary rock?

Carbon dioxide

How long ago did atmosphere become as it is today?

200 million years ago

Nitrogen in air?

80%

Oxygen in air?

20%

Why sun rays come to earth are they short or long?

Short

What cause acid rain?

Nitrogen oxide and sulfuric dioxide

What released nitrogen into the air?

Volcanoes

When did atmosphere begin to form?

4.6 billion years ago

First oxygen?

2.7 billion years ago

Photosynthesis reaction?

6CO2 + 6H2O -> C6H12O6 + 6O2

For humans to drink what must it have low levels of?

Salts and microbes

Water sterilising agents?

Chlorine, Ozone, Uv light

First water filter?

Metal mesh

Second water filter?

Sand and gravel

pH os safe water?

6.5-8.5

What should water be tested for?

Sodium and chloride

What has to be removed from sewage from Agriculture systems and domestic sewage?

Organic matter and Harmful mIcrobes

What waste contains harmful chemicals so must have additional stages?

Organic matter

First stage of water treatment?

Screening

Second stage of water treatment?

Sedimentation

Third stage of water treatment?

Aerobic digestion

What does sedimentation produce as well as water?

Sludge

What happens to sludge?

Anaerobic digestion

What is phytomining?

plants absorb copper ions and are then burnt to produce an ash that contains copper compounds

What is bioleaching?

bacteria absorb copper ions and then produce solutions called leachates which contain copper compounds

What is required for iron to rust?

oxygen and water

What is sacrificial protection?

Coating with more reactive metal?

What is galvanising iron?

Coating with zinc

What is proportion of gold in an alloy measured in?

Carats

What is steel

Iron with carbon

Most common glass?

Soda-lime glass

What is soda lime glass made of?

Limestone, sand and sodium carbonate

wWhat makes up Borosilicate glass?

sand and boron trioxide

Benefit of Borosilicate glass?

Higher melting point

How is low density polythene made?

By heating it at 200 degrees under high pressure

How is high density polythene made?

low temperature and pressure

Haber process forms?

Ammonia

Source for nitrogen and hydrogen?

Air

Catalyst for Haber process

iron

Temperature for Haber process

450

Pressure for Haber process

200 atmospheres

What can be manufactured with ammonia?

ammonium salts and nitric acid

How are Potassium chloride, potassium sulfate and phosphate rock obtained?

Mining

What is phosphate rock treated with?

nitric acid or sulfuric acid

What makes up fertilisers?

NPK

Phosphate and Nitric acid=

Phosphoric acid+Calcium nitrate

Phosphate and Sulfuric acid

Calcium phosphate+calcium sulfate

Phosphate and Phosphoric acid

Calcium phosphate

How are fertilisers made in lab?

Titration and fertilisation

Fertilisers made in industry?

Vats