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Homework Help: . Chemistry Question .

  1. Nov 20, 2004 #1
    We conducted a lab on Friday and today we have to answer a few post lab questions.

    I'm stuck on one question and it asks:

    Does sodium bicarbonate (aka Baking Soda) (NaHCO3) function as an acid or a base? What sort of condition will determine this?

    I know that sodium bicarbonate will function as a base in a typical neutralization reaction such as NaHCO3 + HCl → NaCl + H2O + CO2 .

    However, when will it function as an acid? I cannot seem to find this bit of info anywhere on the net.

    Also, another question, it says here write a balanced chemical equation for the reaction of sodium bicarbonate (baking soda) with phosphoric acid. Does anyone know what it is?

    I think it starts like this but I have no idea what the other products are, well, i know one is going to be a salt, and the other one probably is a gas.

    NaHCO3(s) + H3PO4(aq) --> H2O +

    Thx in advance,

    m!ke :confused:
    Last edited: Nov 20, 2004
  2. jcsd
  3. Nov 20, 2004 #2
    I remember performing a lab with baking soda, quite a few times, in Chemistry last year.

    I don't exactly remember, but, I don't think Baking Soda can be used as an acid. It's a neutalizing agent. If I correctly remember, bases neutalize acids... so it would act as a base, when it is mixed with an acid.

    Don't trust me though, Chemistry was never my strong point :rofl:
    Last edited: Nov 20, 2004
  4. Nov 20, 2004 #3
    yeah me too, but the question's wording seems a bit like it can also act as an acid. Maybe its just me but i'm waiting to hear more comments.
  5. Nov 20, 2004 #4
    bump! anyone know anything about this?
  6. Nov 21, 2004 #5
    bump! its due tomorrow, someone plz answer if they know!
  7. Nov 21, 2004 #6
    dont take what i say as the final word cos i'm still taking Chem. anyways:

    Baking soda acts as a base most of the time except when it's hydrogen concentration is higher than substance it's reacting with (this is a total guess but it'd kinda make sense).

    and for the reaction i'm pretty sure it'd give you water, carbon dioxide and sodium phosphate, Na3(Po4)2. just check though.
  8. Nov 22, 2004 #7


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    In the NaCo3, HCl reaction, you are pairing NaCo3, which is, technically, a salt, with a strong acid. What would happen if you combined it with a strong base?
  9. Nov 22, 2004 #8
    ok i looked up some stuff and apparently, it is possible that baking soda can act as an acid in water, due to a freely avaliable H+ .

    what do you guys think? and its not due tomorrow, its actually due tomorrow from the time i post this, got the due dates wrong =)
  10. Nov 22, 2004 #9
    o and i found out the balanced equation for reaction of baking soda with phosphoric acid if anyone is interested...

    i'm almost 100% sure it is this one:

    3NaHCO3 + H3PO4 ----> 3H2O + 3CO2 + Na3PO4

    (*sorry about subscripts but i duno how to do them here)

    Any corrections plz feel free to comment, thx ya all =)
  11. Nov 22, 2004 #10
    lucifer btw, its Na3PO4, not 2 PO4 since PO4 is an polyatomic ion with charge of -3, but thx for the hint =)
  12. Nov 22, 2004 #11
    for some reason i kept thinking that the sodium ion had a charge of +1(and hence Na3(Po4)2). i'm so stupid lol.
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