[needy]

I hope you can help me with this one.  I did it the way I though it should be done and got a negative answer.

A 15.00 ml aliquot of Tartaric acid (with a formula weight of 150.0866 g/mol) is titrated in a two buret system.  25.03 ml of 0.1427 M NaOH and 2.31 ml of 0.1241 M HCl are used in the titration to a bromocresol green endpoint.  A blank run with a suitable mass of sodium tartrate required 0.43 ml of the 0.1241 M HCl to attain the same endpoint.  Find the concentration of the tartaric acid in mol/L. 

I would greatly appreciate anyone taking the time on this one. 

[Borek]

SHow how you got the negative answer.

[needy]

Did it another way and have no idea if this is correct.
(Vtartaric acid)(cTartaric acid)(#equivalence) + (Vacid)(cHCl)(#equivalence)(1)-(Vblank)(cHCl)(#of equivalence)=(Vbase)(cBase)(#of equivalence)
I have no idea if tartaric acid is giving off 2 equivalences but I assuming it is. 
I got 0.2262M tartaric acid

[Borek]

Seems to me like 0.2226M (62 was a typo?) would be OK for monoprotic acid.

[needy]

Yes it was a type, famous for them.  Thank you for your time.

[needy]

Should have said typo