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xLaser
Nov20-04, 11:59 AM
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:

Physik
Nov20-04, 12:05 PM
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:

xLaser
Nov20-04, 12:47 PM
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.

xLaser
Nov20-04, 04:46 PM
bump! anyone know anything about this?

xLaser
Nov21-04, 05:23 PM
bump! its due tomorrow, someone plz answer if they know!

lucifer
Nov21-04, 08:49 PM
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.

HallsofIvy
Nov22-04, 06:25 AM
In the NaCo[sub]3[sub], HCl reaction, you are pairing NaCo[sub]3[sub], which is, technically, a salt, with a strong acid. What would happen if you combined it with a strong base?

xLaser
Nov22-04, 03:20 PM
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 =)

xLaser
Nov22-04, 03:23 PM
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 =)

xLaser
Nov22-04, 03:48 PM
lucifer btw, its Na3PO4, not 2 PO4 since PO4 is an polyatomic ion with charge of -3, but thx for the hint =)

lucifer
Nov22-04, 04:19 PM
lucifer btw, its Na3PO4, not 2 PO4 since PO4 is an polyatomic ion with charge of -3, but thx for the hint =)

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.