Question

How to write the reaction for this titration process ( cant figure it out)
I started out with borax which i diluted 2x with in a 100ml volumetric flask.
I then titrated it with HCL, what would you guys do as a reaction for it?

Answer 1

well as dilution is not a chemical reaction you just write borax + HCl -> ......

Answer 2

Well it starts off as Na2b407(aq) +2 hcl +5 h20 (l) ---> 4h3BO3(aq) +2NaCl(aq) to a complete ionic that gives me all of those ions breaking down (except for water) and I don't know which one to keep / take out

Answer 3

well why would you take out anything, you write down the reaction and then it doesnt matter that it becomes ionized...

Answer 4

Well I need to get the Net ionic equation, but I don't know whether I keep the Sodium, Oxygen, etc... Even in the product , which product do I keep in my net equation? The Hydrogen borate? or the salt? Thats where I get confuse

Answer 5

ok so you keep it all... just be careful, did you have anhydrous borax or pentahydrate or decahydrate... it would go something like this for decahydrate:
Na2B4O7·10H2O + 2 HCl → 4 H3BO3 + 2 NaCl + 5 H2O

Answer 6

I believe I had pentahydrate, as I had 5 mole of hydrogen. but my net ionic would not use the whole reaction, I mean as im using titration im only looking at the base ( borax) + hcl + h20 . I see my answer but I just don't understand it. It says b407 + 2h(hydronium) + 5h20 ---> 4h3b03.
I have to explain why we end up with b407 and 2hydronium too instead of Hcl

Sorry this answer extrapolated to more :/

Answer 7

ok no problem, now i understand your problem, well you have B4O7(2-) because borax is an ionic compound (salt) which by dissolving becomes ionized and that is why you have ion and H+ because HCl also dissolves and becomes ionized... get it now?

Answer 8

wait why wouldnt you keep the whole borax compound with sodium though? and when you titrate you need to end up with a salt so why dont i keep the Sodium and Chlorine to give me NaCl in the net?

Answer 9

well i would keep them thats what i tried to say... but then you asked to explain why are they in ionized form so i answered... :)

Answer 10

No I understood that and thank you! but my net ionic ( the answer im supposed to get) is B407(2-) (aq) + 2h(+) + water ---> hydrogen borate :/ I understand how to do net ionic with precipitate but not with a whole aqueous reaction

Answer 11

you got me confused now...
Na2B4O7 -> 2Na+ + B4O7-
HCl -> H+ + Cl-
and now you have reaction with B4O7- and H+

Answer 12

Yes thats why im confuse too haha.
It goes like this molecular: Na2b407(aq) +2 hcl +5 h20 (l) ---> 4h3BO3(aq) +2NaCl(aq)
to complete ioniic: 2Na(+) (aq) + 4b (3-)(aq) + 7O(6-) (aq) + 2H(+) (aq) + 2Cl (-)(aq) + 5 H2O(L) ---> 12H(+)(aq)+4B(3-)+12O(6-)(aq) + 2Na(+)(aq) + 2Cl(-)(aq)
to net ionic which Im having trouble to get :/ (well i have the answer but I dopnt understand how my teacher got there)

Answer 13

well teacher just took the B4O7 ion and paired it with H+ iond and water to get it solved

Answer 14

is there a reason why the sodium wasn't used?

Answer 15

sodium wasnt used cause she wrote dissolved or ionized form of borax and acid

Answer 16

AAAAhhhhhh!! but then does it make the B407 a base solution to titrate with the hydronium ion ? and is the 4 hydrogen borate neutral ? O.O I mean if that is what the titration leads to, it must be a neutral compound?

Answer 17

And btw if I have Borax pentahydrate, do I calculat ethe pentahydrate in the molecular weight>?

Answer 18

yes if you have pentahydrate you must use weight of water in molecular weight of borax

Answer 19

why would you think the solution is neutral after titration?!

Answer 20

Because you always titrate an acid with a base or vice and vera and when I use penthalyphelin ( or whatever you werite it) the colour it reaches indicates a pH of almost 7 ( under or above but very close)

Answer 21

ok lets just say it is pH 7 and borax has pH of 9,2 do you have any other questions cause i have to go

Answer 22

No thats all thank you :) Have a good day

Answer 23

not a problem and good luck