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Homework Help: Does salts react with acids?

  1. Aug 16, 2008 #1
    I am new to the concepts of reaction between of Acids, Bases and Salts.
    While learning, I notice that some salts react with acids to form a new salt (and sometimes a new acid is produced), especially in Qualitative Analysis, while some don't even reacts.
    I tried to search the internet about it but to no avail, I've no choice but to ask you guys.

    Why is it that some salts do not react with acids? Is it because of it's solubility in water or other reasons?
    That also contradicts me because [tex]CuCO_3[/tex] + [tex]H_{2}SO_4[/tex] [tex]\longrightarrow[/tex] [tex]CuSO_4[/tex] + [tex]H_2O[/tex] + [tex]CO_2[/tex]
    [tex]CuCO_3[/tex] is an insoluble salt, but it is still able to react with acids.

    Why do salts even react with acids in the first place, that doesn't make sense to me.
    For example if [tex]CaNO_{3}[/tex] reacts with [tex]HCl[/tex] to produce [tex]CaCl_2[/tex]and [tex]HNO_3[/tex], why woundn't the [tex]CaCl_2[/tex] reacts with [tex]HNO_3[/tex] again to form back [tex]CaNO_{3}[/tex] and [tex]HCl[/tex]?
    Last edited: Aug 16, 2008
  2. jcsd
  3. Aug 16, 2008 #2


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    Acids favor the dissolution of salts via the La Chetelier's principle - this is one way.

    For your second question consider which is the better acid.
  4. Aug 19, 2008 #3
    there are many acids, and each one has its own 'strength'. sulphuric acid is a stronger acid than ethanoic acid.

    if you have ethanoic acid reaction with NaOH, you will get the salt sodium ethanoate. but if you then add sulphuric acid to this salt, the weaker ethanoic acid will be displaced by the stronger sulphuric acid to give sodium sulphate and ethanoic acid back.

    HCl is stronger than HNO3 which is stronger than H2SO4.....etc

    HCl will be able to displace HNO3 from a nitrate salt, but HNO3 will not be able to displace the stronger HCl from a chloride salt.

    HCl will displace the weaker carbonic acid from the carbonate as well.
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