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    I was reading through the chapter on oxidation states and I saw a table that states the usual oxidation states of some elements.

    Hydrogen is +1 (except in Metal Hydrides where it is -1)

    What are metal hydrides? Can someone provide a definition and example?

    Oxygen is -2 (except in peroxides and compounds with F, where it is -1)

    What are peroxides?




    Thanks
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    (Original post by xXxiKillxXx)
    I was reading through the chapter on oxidation states and I saw a table that states the usual oxidation states of some elements.

    Hydrogen is +1 (except in Metal Hydrides where it is -1)

    What are metal hydrides? Can someone provide a definition and example?

    Oxygen is -2 (except in peroxides and compounds with F, where it is -1)

    What are peroxides?




    Thanks
    metal hydrides are ionic compounds of metals and hydrogen, such as NaH (made up of Na+ and H-), or MgH2

    peroxides are ionic compounds of metals and oxygen and contain the O22- ion, such as Na2O2
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    (Original post by Plato's Trousers)
    metal hydrides are ionic compounds of metals and hydrogen, such as NaH (made up of Na+ and H-), or MgH2

    peroxides are ionic compounds of metals and oxygen and contain the O22- ion, such as Na2O2
    Thankss.! And I read this on the internet:

    The convention is that the cation is written first in a formula, followed by the anion.

    For example, in NaH, the H is H-; in HCl, the H is H+.

    Is this true for the AQA AS Chemistry specification?
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    (Original post by xXxiKillxXx)
    Thankss.! And I read this on the internet:

    The convention is that the cation is written first in a formula, followed by the anion.

    For example, in NaH, the H is H-; in HCl, the H is H+.

    Is this true for the AQA AS Chemistry specification?
    Correct. Not only the AQA AS specification, but in chemistry generally, at all levels. You would never write CO3Na2, for example, always Na2CO3
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    (Original post by Plato's Trousers)
    Correct. Not only the AQA AS specification, but in chemistry generally, at all levels. You would never write CO3Na2, for example, always Na2CO3
    Thanks
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    (Original post by Plato's Trousers)
    Correct. Not only the AQA AS specification, but in chemistry generally, at all levels. You would never write CO3Na2, for example, always Na2CO3
    What about:

    (CH3COO)2Ca

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    (Original post by charco)
    What about:

    (CH3COO)2Ca

    yes, well apart from that one, obviously (and any others like it) :stomp:
 
 
 
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