Fuel

What substances do you know as a fuel ?

  1. Petrol
  2. Oil
  3. Gas
  4. Coal
  5. Wood
  6. Peat / Turf
  7. Diesel

What have they all in common?

Flammable,

Single use, once we burn them the energy that they give off can not be used again.

When you burn these fuels what happens ??

Heat energy is given off,

this energy comes from the chemical bonds in the Fuel

Chemical energy of a fuel

Are fuels important to Humans ? Why ?

  1. To cook foods (killing bacteria)
  2. Transport using machines
  3. Heat homes (prevents hyperthermia)
  4. To make electricity

A fuel is a material that is used as a source of energy. Burning or combustion of a fuel is a process by which energy is released from many fuels.

What happens when you burn fuels ?

Gives out heat and light energy

Combines Carbon in the fuel with oxygen from the air and gives out Carbon Dioxide

Combines Hydrogen in the fuel with oxygen from the air and gives out water vapour

Burning means we have a fire, fires can only exist if they satisfy the Fire Triangle ....

How to Put out a fire ???

  1. Remove
  2. Remove
  3. Remove

In America before fossil fuels being found, methane in 1821, whale oil was used to light homes.

OC53 recall that fossil fuels are sources of hydrocarbons, and that they produce CO2 and H2O when burned

Recall fossil fuels are sources of hydrocarbons

Fossil fuels are found in the ground.

Fossil fuels are made from Plant (& animal) remains.

The oil that comes out of wells is called crude oil. This crude oil is a raw material.

It is called crude as it has not yet been refined into useful products.

Gasoline is (mostly) a mixture of hydrocarbons. The name "hydrocarbons" suggests that chemically they include Hydrogen and Carbon.

burning methane

Methane + Oxygen → Water + Carbon Dioxide

So the products of combustion of (gasoline) fuels in air are primarily water and carbon dioxide.

Homework Pg226 q 1-4

  • Hydrocarbons contain a lot of energy. Many of the things derived from crude oil like petrol, diesel fuel, paraffin wax and so on take advantage of this energy.
  • Hydrocarbons can take on many different forms.
  • The smallest hydrocarbon is methane (CH4), which is a gas that is a lighter than air. The natural gas that is burned in your house is Methane.
  • The shorter the chain the more energy that the HydroCarbon can release,
  • Longer chains with 5 or more carbons are liquids.
  • Very long chains are solids like wax or tar.
  • By chemically cross-linking hydrocarbon chains you can get everything from synthetic rubber to nylon to the plastic in tupperware.
  • Hydrocarbon chains are very versatile!

follow on to see an animation of fractional distillation

http://science.howstuffworks.com/environmental/energy/oil-refining4.htm

follow on for cracking, the way the petroleum industry has made useless chains into desirable and profitable products.

and that they produce CO2 and H2O when burned

Prove that CO2 and H2O are given off during burning a fuel

You may already have learned about a test for Water .... mmm..... what was is again

C______ C______ changes colour from _____ when it is dry to _______ when it is in the presence of Water

L_________ goes cloudy or milky when ________ _________ is passed through it

click on image to see a larger version

The Ice & Water cools down the gas that comes from the Candle, some liquid condenses on the side of the U tube, test this liquid with white Copper Sulphate, it goes Blue, this is proof the liquid is water (H2O)

Limewater is a test for Carbon Dioxide, it goes Milky when CO2 passes through it. It goes milky after a little while, thus shows that burning HydroCarbons releases Carbon Dioxide

Burning fuels that do not combust properly can result in Carbon Monoxide being released

http://www.carbonmonoxide.ie/htm/whatis.htm

On average, crude oils are made of the following elements or compounds:

  • Carbon - 84%
  • Hydrogen - 14%
  • Sulfur - 1 to 3% (hydrogen sulfide, sulfides, disulfides, elemental sulfur)
  • Nitrogen - less than 1% (basic compounds with amine groups)
  • Oxygen - less than 1% (found in organic compounds such as carbon dioxide, phenols, ketones, carboxylic acids)
  • Metals - less than 1% (nickel, iron, vanadium, copper, arsenic)
  • Salts - less than 1% (sodium chloride, magnesium chloride, calcium chloride)

do questions q 1-8

OC55 describe the role of the combustion of fuels and of SO2 in the production of acid rain, and describe the effects of acid rain

On average, crude oils are made of the following elements or compounds:

  • Carbon - 84%
  • Hydrogen - 14%
  • Sulfur - 1 to 3% (hydrogen sulfide, sulfides, disulfides, elemental sulfur)
  • Nitrogen - less than 1% (basic compounds with amine groups)
  • Oxygen - less than 1% (found in organic compounds such as carbon dioxide, phenols, ketones, carboxylic acids)
  • Metals - less than 1% (nickel, iron, vanadium, copper, arsenic)
  • Salts - less than 1% (sodium chloride, magnesium chloride, calcium chloride)

When fuels are burned in Oxygen, they release more than CO2 and H2O, they also burn some Sulphur that is also contained in the fuels. This creates sulphur dioxide SO2.

The gas that is most abundant in air is Nitrogen, this also can react in the intense heat of an engine or furnace to produce Nitrous Oxides NOx. Both SO2 and NOx react with Water in the atmosphere to form acidic solutions, Sulphuric acid and Nitric acid.

These are very strong acids. These acids become apart of the rain, and fall many hundreds or thousands of kilometers from where the cause of this pollution is located.

Carbon Monoxide can also be created in this process

Modern cars include a catalytic converter in the exhaust system. The converter gives a "second chance" for these compounds to be fully burned before they are released into the air.

OC56 describe the effect of acid rain on limestone and on plants

on limestone

Limestone dissolves in Acid rain , leading statues and buildings to lose their definition/shape.

limestone is http://en.wikipedia.org/wiki/Limestone Calcium Carbonate, http://en.wikipedia.org/wiki/Calcium_carbonate is also the same as blackboard chalk

lets experiment on that

How could we ??? What could we measure ??? What apparatus would we need ??

on plants

The Acid rain reacts with minerals from the earth that are required by plants for healthy growth. As the plant loses access to these minerals the growth slows and eventually stops.

The acid rain also make the soil more acidic, which some plants cannot survive in as they prefer either neutral or more alkaline soils. In naturally acid areas, the pH levels can become too low for plants to survive.

on animals

Fish that live in lakes affected by acid rain die as the plankton / algae they eat is unable to survive in the low pH water.

Homework devise an experiment to see the effect of acid rain on limestone / plants. Include a control.

Places significantly impacted by acid rain around the globe include most of eastern Europe from Poland northward into Scandinavia.

OC57 understand that natural gas is mainly methane

Test yourself here

http://www.sciencequiz.net/jcscience/jcchemistry/fossilplastic/fossilplastic.htm

The Kyoto Protocol calls for the introduction of biofuels on the transport fuel market in order to reduce greenhouse gas emissions. This makes Lurgi your ideal partner thanks to its longstanding experience and outstanding references.

http://www.lurgi.info/website/index.php?id=19&L=1

This is very unusual, what do you think about this?

Global Warming

https://sites.google.com/site/hcsgreenschools/whywearedoingthis

http://blog.sccscience.com/2010/09/what-are-real-alternatives-to-oil.html