Overall quick test Flashcards
State the composition of the atmosphere.
78% nitrogen, 21% oxygen, 1% other gases (mainly argon with small amounts of other gases including water vapour and carbon dioxide)
List the stages involved in the most probable theory of the evolution of the atmosphere.
The early atmosphere of carbon dioxide and water vapour formed from volcanoes. Atmospheric water vapour condensed to form the oceans. Photosynthetic organisms used up carbon dioxide and released oxygen. Carbon dioxide dissolved in the oceans and formed sedimentary rocks and fossil fuels.
Name the two natural processes that remove carbon dioxide from the atmosphere.
Photosynthesis and dissolving in the oceans.
Explain why combustion is a type of oxidation reaction.
Combustion is when a fuel reacts with oxygen (to release energy)
What does the term ‘hydrocarbon’ mean?
A hydrocarbon is a compound made only from carbon and hydrogen.
Give 3 ways to reduce pollution from power stations.
Using less electricity, removing sulfur from the fuel being used, removing sulfure dioxide and particulates from the gases released by the power station.
Give 4 ways to reduce pollution from cars.
Any 4 from:
More efficient engines, low-sulfur fuels, catalytic converters, using public transport more, legal limits for emissions
Explain how NO[x] gases are formed. (HT)
Atmospheric nitrogen is oxidised by atmospheric oxygen at high temperatures to form nitrogen monoxide (NO), which is further oxidised to form nitrogen dioxide (NO[2]).
Name 2 natural materials and 2 synthetic materials.
Natural materials = any 2 from: silk, wool, cotton, paper
Synthetic materials = any 2 from plastics such as poly(ethene), polyesters, nylon, PET
Name the process used to separate crude oil into useful hydrocarbons.
Fractional distillation
Explain the link between molecule size and boiling point.
The larger the molecule, the stronger the intermolecular forces and the more energy that is needed to overcome the forces, so the higher the boiling point.
Give a use for kerosene/paraffin.
Fuel for aeroplanes/central heating/camping lanterns
What is the effect on the properties of a plastic of cross-linking the polymer molecules?
Cross-linking makes a plastic stiffer and harder and it increases its melting point
What is a plasticizer and what does it do to the properties of a polymer?
A plasticizer is a small molecule that fits between polymer chains and weakens the intermolecular forces, making the polymer more flexible
What is nanotechnology?
Nanotechnology is the study and manipulation of very small particles
Give an example of how nanoparticles can occur naturally.
In sea spray (also accept ‘particulate carbon produced by combustion of fuels’.)
Name 3 mineral resources found in Britain.
Coal, salt and limestone
Name 3 processes that have been involved in creating Britain’s mineral resources.
Any three from mountain building, erosion, sedimentation, dissolving, evaporation
State 2 things that salt is used for.
Any 2 from as flavouring and preservation in food, to treat roads in winter, as a source of chemicals
Why is excessive salt in the diet bad for you?
It can cause high blood pressure
Name 3 products from the electrolysis of brine (salt water).
Hydrogen, chlorine and sodium hydroxide
What is meant by the term ‘electrolysis’?
Splitting up a liquid or dissolved compound using electricity
Give one use of chlorine.
Any suitable answer: to disinfect water, as a bleach, in the manufacture of plastics
Briefly describe what happens in a life cycle assessment.
Any suitable answer: each part of the life cycle (production of materials, manufacture, use and disposal) is assessed for impact on resources, energy requirements, and environmental impact.
