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So how do you know when a chemical is an acid or not? I know that an

  1. Aug 28, 2011 #1
    So how do you know when a chemical is an acid or not? I know that an acid is a compound that, when dissolved, yields H atoms, but does that mean than any compound with H in it is (or has the potential to be) an acid?

    For example:

    HNO2, I put down that it was Hydrogen Nitrite, but the actual answer is Nitrous acid. How do I know whether or not to name it as an acid?
     
  2. jcsd
  3. Aug 28, 2011 #2
    Re: Acids?

    Calling HNO2 as hydrogen nitrite is not wrong (likewise, we can call HCl as hydrogen chloride). I suppose it is only when the substance, that has the description of an acid, is in water (aqueous) do we call it an acid.

    I suppose you would just have to remember which are acids and which aren't. Usually, whatever inorganic compound has a hydrogen atom, or compounds with SO3H and COOH are acids. Can't remember others. =P
     
  4. Aug 31, 2011 #3
    Re: Acids?

    There are several different definitions of acids. Brønsted being one guy who defined an acid as a substance that loses/gives/donates H+ (proton donor). Lewis is another one, and defines acid as a substance that is an electron-pair acceptor.

    There probably are other definitions as well. And let's not forget the organic functional group
    -COOH.
     
  5. Aug 31, 2011 #4
    Re: Acids?

    I think the lewis definition is the best since the other definitions can be explained by the accepting of electrons
     
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