• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Burning Fuels - Fuels are substances that release energy when they react with oxygen. This reaction is known as burning, or combustion. Combustion is an exothermic reaction

Extracts from this document...

Introduction

Fuels Burning Fuels Fuels are substances that release energy when they react with oxygen. This reaction is known as burning, or combustion. Combustion is an exothermic reaction. The energy which is given out by combustion is used in a variety of ways: > > Energy from burning methane in gas cookers is used for heating. > > Energy from burning candles is used for lighting. > > Energy from burning petrol in car engines is used to create motion. > > Energy from burning coal in power stations is used to generate electricity. The oxidation of fuels gives chemical products, as well as energy. Most of the fuels used today are hydrocarbons. When hydrocarbons burn, carbon dioxide and water are the usual chemical products: e.g. CH4(g) + 2O2(g) � CO2(g) + 2H2O(l) Incomplete Combustion If the air/oxygen supply for burning is limited, then incomplete combustion may occur. The combustion will not only be less exothermic, but the chemical products will also differ - carbon monoxide is formed instead: e.g. CH4(g) + 11/2O2(g) ...read more.

Middle

* * Natural Gas The main constituent of natural gas is methane (CH4). Traces of ethane, propane, nitrogen and other gases are also present. Gaseous fuels are easy to ignite, and can be burned very efficiently. They are harder to store and transport, and gas leaks can be very dangerous. Other Fuels * * Ethanol (methylated spirits) (Refer to 'Chemicals from Oil' notes.) * * Wood * * Hydrogen - has a high 'energy density' and is a very clean burning fuel; the only combustion product is water: 2H2(g) + O2(g � 2H2O(l) Air Pollution One of the problems with burning fuels is the production of pollutants. Most of these pollutants are gases, so they diffuse into the atmosphere, where they can have various effects on the environment. Pollutants from burning fuels include: * * Carbon dioxide, CO2 * * Carbon monoxide, CO * * Sulphur dioxide, SO2 * * Oxides of nitrogen, NOx * * Unburned hydrocarbons * * Lead compounds * * Smoke Effects of these pollutants include: * * Acid ...read more.

Conclusion

This extra carbon dioxide may cause the average temperature of the earth to increase by 2-3 oC, which could have serious consequences, like flooding due to a rise in sea level. This problem is called 'global warming'. The Hole in the Ozone Layer The only pollutants in the table above which are not connected with the burning of fuels are the chlorofluorocarbons (CFCs). These compounds have been used extensively as refrigerants, propellants and cleaning solvents in the twentieth century. The ozone layer protects us from the sun's harmful UV radiation, which can cause sunburn and skin cancer. In the 1980's it was discovered that a large hole was developing in the ozone layer, and it was thought that CFCs were responsible. These compounds are very unreactive and so gradually diffuse into the upper atmosphere. There they are broken down by ultra-violet rays from the sun giving chlorine atoms ('chlorine radicals') which are highly reactive. These chlorine radicals catalyse the breakdown of ozone into normal oxygen: 2O3(g) � 3O2(g) (For further details about these pollutants, and their environmental impact, see handout.) ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Organic Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Organic Chemistry essays

  1. Marked by a teacher

    Iron ore: processes and History

    3 star(s)

    The Winfield, (County Durham), coke ovens generated heat for a copper oxide plant specifically built nearby in 1915AD. Carbon monoxide is widely used in the reduction process; the burning of coke produces the carbon monoxide. On the Moon, on the other hand, many processes such as silicon carbide aluminium reduction will yield large quantities of carbon monoxide.

  2. The Energy Content Of Different Fuels

    will go through a number of stages, these are: * Calculate the temperature rise of the water. By finding the difference between the beginning temperature of the water and taking it away from the final temperature of the water. This will be in ?C.

  1. THE LINK BETWEEN CARBON ATOMS IN A FUEL AND THE ENERGY IT RELEASES.

    fit and the other is a bar chart graph that shows the relationship between the carbon atoms and the energy they release. NO. of carbon atoms 1 2 3 4 5 Kj/mole 220.44 437.96 674.37 911.05 1180.97 After plotting the graph of the values above, there is a nice straight line on the graph.

  2. To Investigate the Combustion of Fuels

    make it a fair test, I will always keep the amount of water the same, at 100ml; the temperature of the water at the start will be the same; the amount the temperature must rise by the same, at 10o; the distance from the bottom of the conical flask to

  1. Hydrocarbons As Fuels.

    If gases such as methane and hydrogen are to be used as alternatives to petrol in vehicles, the problems of storage of large amounts of gas must be solved. What is fractional distillation? The process of fractional distillation is used to separate the components of a mixture of liquids by means of the differences in their boiling temperatures.

  2. Comparing fuels

    height of the test tube away from the flame * The time of burning * The amount of water in the test tube being heated * Type of beaker, glass * Same set of scales The variable that has to be changed is...

  1. Investigating energy when fuels burn.

    Preliminary Results Alcohol How long burned for (minutes) Methanol 4:30 Ethanol 6:47 Propanol 5:41 Butanol 7:02 From looking at the table we can see that all the alcohols burn for 4:30 minutes or more, this means I shall therefore allow the alcohols to burn for fours minutes each in the experiment.

  2. GCSE Chemistry Revision Notes - everything!

    The temperature at which a liquid becomes a gas is called the boiling point. There are forces of attraction between particles. In a solid the forces are strong, in liquids, they are weaker, allowing the particles to slide over each other and in gases- the forces are very weak.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work