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  1. Standard member najdorfslayer
    The Ever Living
    28 Mar '09 10:10
    1.
    Does anyone know the equation for the 'test for nitrates'

    Sodium nitrate + sodium hydroxide + aluminium > ?


    P.S. I know the answer but I think it is difficult.

    2.
    What is formed when sodium reacts with nitric acid?

    sodium + nirtic acid > ?
  2. Subscriber AThousandYoung
    Do ya think?
    28 Mar '09 10:20
    Originally posted by najdorfslayer
    1.
    Does anyone know the equation for the 'test for nitrates'

    Sodium nitrate + sodium hydroxide + aluminium > ?


    P.S. I know the answer but I think it is difficult.

    2.
    What is formed when sodium reacts with nitric acid?

    sodium + nirtic acid > ?
    I don't know either. Want me to figure it out using Google?
  3. Standard member najdorfslayer
    The Ever Living
    28 Mar '09 10:22
    I think I know them both,,(I had to work them out), trust me I tried google I found nothing
  4. 28 Mar '09 17:49
    Originally posted by najdorfslayer

    2.
    What is formed when sodium reacts with nitric acid?

    sodium + nirtic acid > ?[/b]
    I'm not sure, but doesn't it produce a salt, like sodium nitrate?
  5. Standard member najdorfslayer
    The Ever Living
    28 Mar '09 18:06
    Originally posted by dannyUchiha
    I'm not sure, but doesn't it produce a salt, like sodium nitrate?
    Yes definately, but what else
  6. 28 Mar '09 18:13
    Originally posted by najdorfslayer
    Yes definately, but what else
    Hydrogen?

    I think it goes like:

    Na2 + 2HNO3 -> H2 + 2NaNO3
  7. Standard member najdorfslayer
    The Ever Living
    28 Mar '09 18:33 / 2 edits
    Originally posted by dannyUchiha
    Hydrogen?

    I think it goes like:

    Na2 + 2HNO3 -> H2 + 2NaNO3
    Well metals usually react with acids to produce salt + hydrogen

    E.g. magnesium + hydrochloric acid > magnesium chloride + hydrogen.

    However as nitric acid is an oxidising acid I was thinking maybe the N is reduced rather than the H!
  8. 28 Mar '09 20:09
    Originally posted by najdorfslayer
    Well metals usually react with acids to produce salt + hydrogen

    E.g. magnesium + hydrochloric acid > magnesium chloride + hydrogen.

    However as nitric acid is an oxidising acid I was thinking maybe the N is reduced rather than the H!
    How do you propose the reaction would occur?
  9. Standard member najdorfslayer
    The Ever Living
    28 Mar '09 22:37 / 5 edits
    Originally posted by dannyUchiha
    How do you propose the reaction would occur?
    I know that nitric acid rarely produces hydrogen when it reacts with metals (excpet for magnesium and calcium,when cold and dilute)

    In reality the products you obtain usually depends on the temperature and the concentration of the acid used.

    A common reaction is copper with conc.nitric acid

    Cu + 4HNO3 -> Cu(NO3)2 + 2NO2 + 2H2O

    However I think this is only for metals low in the electrochemical series (e.g. Cu & Pb).

    However becuase sodium is such a good reducing agent, maybe it will reduce the N further, here are the possible options. I would imagine you need to look at the standard reduction potentials.

    1. Na + 2HNO3 -> NaNO3 + NO2 + H2O
    (Here nitrate reduced from +5 to +4 in nitrogen dioxide)

    2. 3Na + 4HNO3 -> 3NaNO3 + NO + 2H2O
    (Here nitrate reduced from +5 to + 2 in nitrogen monoxide)

    3. 8Na + 10HNO3 -> 8NaNO3 + 5H2O + N2O
    (here nitrate reduced from +5 to +1 in dinitrogen oxide)

    4. 6Na + 8HNO3 -> 6NaNO3 + 2H2O + NH3OHNO3
    (Here the nitrate reduced from +5 to -1 in hydroxylammoniumn ions)

    5. 8Na + 10HNO3 -> 8NaNO3 + NH4NO3 + 3H2O
    (Here the nitrate reduced from +5 to -3 in ammonium ions)

    Trust me you wont find this in any books or anywhere on the internet, that is why I asked the question!

    It's all self worked out

    My gut feeling is number 5