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!You should only do this practical exercise when under the supervision of a teacher

Pages

1Where is Mars?2How long will it take to get to Mars?3Getting to Mars4How do rockets get off the ground?5Producing Thrust6What happens when rocket fuel burns?7Your mission to Mars!8Our need for oxygen9How oxygen gets to our cells10The effects of gravity11How low gravity affects bones12Preventing bones and muscles from becoming weak13Living and working in space14What do astronomers know about Mars?15A space-craft view of Mars16Exploring Mars17Energy for exploration18The rocky surface of Mars19More about the surface of Mars20The Martian atmosphere21The importance of water22The water cycle on Earth23Is there water on Mars?24Surviving on Mars25Your Martian home26Farming on Mars27Soil on Mars28Plants for Mars29Getting energy on Mars30Where will you go next?

Practicals

1Modelling the solar system in the school yard2Rocket Practical3Investigate the Energy in Fuels4Making a Telescope5What factors affect the output of a solar cell?6Modelling Diffusion7Examining Slides of Blood8What bones are like without calcium salts9Flame Test to Identify Metals10The Different States of Water11Water Purification for Human Consumption12Factors Affecting Germination13Solar Cells for Devices14Mars Bingo
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Practical 3

Investigate the Energy in Fuels

In this practical exercise, you will find out how much energy is contained within one or more fuels. These fuels will probably be alcohols: you may have heard of alcohol being present in drinks such as beer and wine, but in fact there are several different types of alcohols, and they are made of molecules which have chemical energy locked within them.

What will you need? (Apparatus)

Practical Exercise Image

Safety

These safety points mainly tell you about hazard. You will need to think about the risk(s) this might pose, and how you can minimize the risk.

What do you need to do? (Method)

  1. Make sure you listen to guidance from your teacher about details of the method and safety procedures
  2. Measure 100cm3 of cold tap water into a conical flask.
  3. Clamp the flask at a suitable height so that a spirit burner can easily be placed below (as in the apparatus diagram).
  4. Weigh the spirit burner (and cap) containing the alcohol and record this mass and the name of the alcohol.
  5. Record the initial temperature of the water in the flask.
  6. Place the spirit burner under the flask and light the wick.
  7. Allow the alcohol to burn (combustion) so that it heats the water. Allow the temperature of the water to rise by 40°C.
  8. Replace the cap to extinguish the flame.
  9. Re-weigh the spirit burner and cap, and record this mass.
  10. Work out the mass of alcohol used by subtracting the mass in step 8 from the mass in step 3.
  11. Now start all over again (using a fresh volume of cold tap water) with another alcohol in a different spirit burner. Make sure that in each case you let the temperature rise by the same amount, i.e. 40°C.

What will you see? (Results)

You will be investigating several different alcohols. For each one, you need to write down:

What would be the best way of recording this information?

What happened, and why? (Conclusion):

Here are some points to think about: