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    I've been told you add dilute ammonia to get a while precipitate (Of magnesium hydroxide?), but wouldn't this be the same for say...Calcium?
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    never heard of that one before...maybe a flame test? (brilliant white flame)
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    Yeah, I never heard of that before either Works fine according to Wikipedia, just I'm not sure calcium doesn't do the same :P Magnesium doesn't give off white light - it gives off some form of non-visible light (UV I think). I read that the white light is from its reaction with oxygen :P

    Reminds me of my first chemistry lesson though - we were given a strip of magnesium each, and a bunsen burner. Told to do nothing with it which naturally meant try and melt the strip xD Oh well...
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    Yeah, but unless you're burning the magnesium in a special atmosphere, when it burns it will react with oxygen present in the air, that's what combustion is. Hence the result of the flame test is just stated as a white flame. (I guess really, the results of the flame tests are the results of combusting with oxygen, but it's easier just to say burned)
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    test for magnesium is add ammonia and a white precipitate forms
    (add more and if it dissolves its aluminium)
    but yeah calcium will do the same, so you do a flame test and calcium has a "brick red" (thats the textbook definition but it looks orange tbh) flame whereas magnesium doesnt change (the white flame is when you burn magnesium in air/oxygen im pretty sure magnesium doesnt have a flame test)
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    If you burn magnesium in air you get a bright white flame, if you want to detect the presence of a magnesium ion in a compound this won't work as the electronic transisitons do not give out visible light. Chemical tests are silly
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    (Original post by fieryiceissweet)
    but yeah calcium will do the same, so you do a flame test and calcium has a "brick red"
    Oh, thanks Didn't think of testing for Calcium to show it wasn't that.
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    no worries
    i accept visa, mastercard, +rep...

    :P
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    (Original post by Zygroth)
    I've been told you add dilute ammonia to get a while precipitate (Of magnesium hydroxide?), but wouldn't this be the same for say...Calcium?
    I have heard of it. It's in the edexcel book. So if you are doing edexcel learn it. (Im taking AS level too - it's for paper 3B or the practical) - the theory behind does not come until you have done A2 (does not deal with Mg directly but other transition metal with NH3 and OH-)
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    (Original post by EierVonSatan)
    never heard of that one before...maybe a flame test? (brilliant white flame)

    its looks white but my teacher said its 'colourless'
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    burning magnesium (the solid) gives a brilliant white flame, burning a salt of magnesium (so its ion) is colourless
 
 
 
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