1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Hi Guest, welcome to the TES Community!

    Connect with like-minded professionals and have your say on the issues that matter to you.

    Don't forget to look at the how to guide.

    Dismiss Notice

Teaching extraction of metals

Discussion in 'Science' started by deborahharris89, Mar 14, 2012.

  1. I have a lesson observation for my NQT next week, teaching AQA AS Chemistry. Unfortunately the topic is extraction of metals. How can I make this not mind-numbingly dull. All the resources I can find are just labelling blast furnaces and balancing equations. There's got to be a way to make this topic more interesting...
     
  2. I have a lesson observation for my NQT next week, teaching AQA AS Chemistry. Unfortunately the topic is extraction of metals. How can I make this not mind-numbingly dull. All the resources I can find are just labelling blast furnaces and balancing equations. There's got to be a way to make this topic more interesting...
     
  3. I am not a Chemistry teacher but, when I did this (ages ago) I discovered that the more reactive the metal, the more recently (in terms of history) it was discovered & that the extraction methods depend on the reactivity of the metal and the availablility of technology.
    Maybe I am mis-remembering stuff but it was a real eye opener for me to see that Aluminium needs electricity (lots of energy) for extraction, and that the metal is a more recent addition to our arsenal of resources but that Iron (discovered ages ago) can be extracted using thermal energy - a resource that has been around for ages.
    Can you link the energy required to break bonds to the methods of extraction, the dates of discovery of the metals and the technology available? There may be a graph or timeline somewhere on the interweb. Maybe, given the right clues, the pupils could work this out for themselves?
     
  4. Rhysboy

    Rhysboy New commenter

    There is an activity in the 21st Century scheme.
    It's extracting metals with carbon. I did it as a demo a few years back. Let me now if you want more details.
    You could also demo the electrolysis of lead bromide - again from the C21 scheme.
    Follow these up with a bit of theory and balanced equations, possibly determining reacting masses, etc (depending on the scheme) and that should take a lesson.
     
  5. Rhysboy

    Rhysboy New commenter

    <font size="2">There are a few activities in the 21st Century scheme.</font><font size="2">Firstly you could do extracting metals with carbon, such as iron oxide, copper oxide etc. I did it as a demo a few years back. I had to heat it for a fair bit of time before hand if I remember correctly. Let me know if you want more details. (I could email you the resources if need be). </font><font size="2">You could also demo the electrolysis of lead bromide - again from the C21 scheme. </font><font size="2">Follow these up with a bit of theory and balanced equations, possibly determining reacting masses, etc (depending on the student ability and the scheme) and that should take a lesson. </font>
     
  6. The whole reason hat extraction of metals is on the syllabus really is that it is a practical demonstration of redox in action. If you take that as the basis of your lesson then it becomes less dull and you concentrate on the basic skills and understanding the students need. You've not said which part of metal extraction you're doing - Iron? Aluminium? Tungsten?
     
  7. Beware of taking 21C stuff for an AS lesson. You may fine it is not the right level. Check the AS syllabus, look at a few past papers on the topic & plan a lesson that meets the requirements with a bit of extra content / info if possible, to stretch the pupils.
    A quiz at the end with personal white boards so you can see what they have understood possibly?
     
  8. Rhysboy

    Rhysboy New commenter

    Yes, I missed the AS level part in the original message.
     
  9. blazer

    blazer Star commenter

    Back in the day we would reduce metal compounds using a carbon block, bunsen burner and blowpipe! I bet H&S won't allow that anymore even though when we did it we had 1970s hairstyles!

    You can put Iron oxide and carbon in a crucible and heat it for 10 minutes. Show that the oxide and carbon are not magnetic but that after heating (and allowing to cool) a magnet will pick out iron from the crucible. You could probably show a loss in mass as well because the CO2 formed has escaped.
    If you can find a clip on youtube the BBC show Chemistry a Violent History has a demo of how Davy electrolysed potash to produce potassium.

    It was KS3 but there used to be a Chemistry in Action program called Earth, fire and metals that would be a good 20 minute starter

     
  10. Mangleworzle

    Mangleworzle Star commenter

    You can get copper from the carbonate (malachite ore) with a bunsen burner. Demo iron with blowpipe and carbon block if possible, youtube clip of aluminium or something more reactive.
    Tie to how powerful (probably the wrong word) the reducing agent/conditions have to be.
     
  11. phlogiston

    phlogiston Star commenter

    A good quickie practical is to moisten the end of a matchstick, dip in some iron (III)oxide and heat in the hot bit of a bunsen flame. There will be a small amount of iron that can be picked up with a magnet. This can then move into a more detailed account of how it's really extracted, why CO is a good reducing agent (as a gas it spreads about).
    P
     

Share This Page