Primary Standard + NaOH finding concentration (1 Viewer)

[smith93]

hey all,

so we're doing titration in class and ive got a question about the calculations..

We're using oxalic acid as our primary standard, and we need to use it to find the concentration of our NaOH, which we made also.

So my data is,
i put 1.58g of oxalic acid in to fill a 250mL flask. so that makes it ~0.013moles.
then the molarity of that solution is 0.05 molar.
while titrating the NaOH into 25mL of the oxalic acid, it took 41.8cm^3 to reach it's equivalence point.

with that information how do i then calculate the concentration of the NaOH?!!

Thanks HEAPS!!

smithy

 

[FCB]

Firstly you have to write a balanced equation or else it will muck up your calculations.
So i think you have a total of 0.1 molar NaOH (Were starting this at school now so i am not 100% sure)
and you have a volume so you have 3 out of 4 parts. You can now solve for 'n' (i think)

So is the answer 4mol L^-1 (most likely not.)

 

[FCB]

I have no idea what you do about the equivalence point thing...

 

[jamesfirst]

Isn't equivalence point got to do with the titration of the HCl and NaOH..

I'm still doing this in class so I probably can't answer it :S


btw what's an oxalic acid ?? The chemical formula for it.


I don't know what the hell 41.8 x10^3 cm thing is... Do you mean the scale of the burette ?

To solve these questions:

use two formulas : n = m/M and C = n/V