Topic 5 - Fuels Flashcards

Question

How does the earth control its temperature

Answer 1

The temperature of the earth is a balance between the heat from the sun and the heat it radiates back into space. Gases in the atmosphere such as carbon dioxide water vapour and methane act like a layer of insulation and stop some of the radiating into space.

Answer 2

Remove sulphur from fuels so there is less acid rain Acid gas scrubbers in power stations (limestone removes it) Cars are fitted with catalytic converters to clean up exhaust gases. Reduce the amount of fossil fuels we use.

Answer 3

We affect the amount of greenhouse gases by deforestation, burning fossil fuels and other things. This increases the amount of green house gases, heating up the earth.

Answer 4

Stop chopping down trees Reduce the amount of fossil fuels we burn Iron seeding Converting waste carbon dioxide into hydrocarbons.

Answer 5

Plants need iron for photosynthesis. By injecting iron into the upper ocean you promote the growth of phytoplankton. These blooms of phytoplankton absorb carbon dioxide from the atmosphere for photosynthesis.

Answer 6

``` H | H-C-H | H ```

Answer 7

``` H H | | C=C | | H H ```

Answer 8

Because they have a double bond there is a space bond so other elements can join

Answer 9

Cracking is a from of thermal decomposition which just means breaking molecules down into simpler molecules by heating them. Using this method you can shorten hydrocarbons to make them into something more useful.

Answer 10

There is more of a demand for shorter hydrocarbons do we need to shorten some. Also it produces alkenes which can be used to make plastics.

Answer 11

It's stretchy and light so can be used to make plastic bags hose pipes and laminating paper

Answer 12

It is tougher flexible so can be used to make thermal underwear, carpets and plastic containers.

Answer 13

It's unreactive flame resistant and very resistant to wear. It can be used as a non stick coating for pans.

Answer 14

It's flexible and resistant to wear so can be used for clothing electric cables and pipes

Answer 15

They are non-biodegradable which means they aren't broken down by microorganisms so they don't rot. If you burn some plastics they give off toxic gases. It's best to recycle them as this conserves resources.

Answer 16

fuels used for transport such as bioethanol or biodiesel that are made from biomass materials. These fuels are usually blended with fuels made from crude oil but can be used on their own.

Answer 17

Biodiesel burns in an ordinary diesel engine with them having to be modified. Bioethanol burns cleanly and the waste from manufacturing can be used as food for livestock. they are a renewable energy source. they don't contain sulfur so don't cause acid rain. Carbon neutral

Answer 18

Petrol engines need to be converted. Transporting it and using farm machinery to harvest them increases the net CO2 released. Large areas of tropical forest are being cleared to grow crops. An increase in the growth of biofuels means less land is available for food.

Answer 19

Exam mark scheme ``` Burning considerations • ignite easily • burn easily • release a lot of /sufficient heat energy when it is burnt Usage considerations • be safe to use • be safe/easy to transport • be {safe/easy/convenient} to store • be reasonably cheap Supply considerations • readily available/good supply • be renewable/sustainable/not finite Products considerations • not produce (much) solid/ash when burnt • not produce much/any smoke • contain little/no sulfur • not produce {toxic/harmful} gases/fumes • carbon neutral • not produce too much carbon dioxide or other named gas such as sulfur dioxide or greenhouse gases ```

Answer 20

microorganisms. They are used to decompose living organisms' waste or dead plants to create biogas which can be used as a fuel.

Answer 21

It can be burned to heat water, used in central heating systems, power a turbine, used as a fuel for cars and buses.

Answer 22

``` It is renewable. The plants which are decomposed can be replaced quickly. Carbon neutral Clean fuel Cheap Readily available ```

Answer 23

Carbon dioxide and water

Answer 24

using yeast to ferment sugars

Answer 25

where there is plenty of fertile land and good weather for growing crops.

Answer 26

Advantage: less crude oil being used, carbon neutral Disadvantage: lots of land needed to grow crops so not as much room for food. Uses a lot of energy.

Answer 27

water and energy

Answer 28

An electrical cell thats supplied with a fuel and oxygen and uses energy from the reaction between them to generate electricity.

Answer 29

80% efficient FC: electricity generated directly from reaction. Not much energy lost as heat. No moving parts so energy isn't lost through friction. Doesn't produce any conventional pollutants

Answer 30

Hydrogen is a gas so takes up more space to store than liquid fuels. Explosive Hydrogen fuel is often made from hydrocarbons (from fossil fuels) or by electrolysis of water (which uses electricity that is often created by using fossil fuels)