[Tidus41390]

New question:

Mass of flask - 116.25g
Mass of flask plus vinegar - 121.05g
Mass of vinegar - 4.8g
Buret reading of NaOH, final - 52.5mL
Buret reading of NaOH, initial - 5mL
Volume of NaOH used - 47.5mL
Molarity of NaOH - ??

[english]

I guess I'll take this one off of Borek's shoulders.   


If you have 4.8 grams of vinegar (acetic acid), then you know how many moles of vinegar you have. 

Your NaOH volumes correspond to your end point.  This means you have a small excess of HO^- ions and water in solution (there are other species in solution as well, but we don't care); the tiny excess of hydroxide ions actually allow you to see your end point. 

Since your solution is neutralized, meaning both acidic and basic components have formed water in solution, x moles of NaOH reacted with x moles of acetic acid.  Since the molar ratio is 1:1, and you know how many moles of acetic acid you had at the beginning, you know that this must be the number of moles of NaOH you have as well. 

So now you have two pieces of information:
(1) volume of NaOH added
(2) number of moles of NaOH

You have a concentration then.

[Borek]

I guess I'll take this one off of Borek's shoulders.   

Thanks 

If you have 4.8 moles of vinegar (acetic acid), then you know how many moles of vinegar you have.

You sure you don't need help?

[english]

If you have 4.8 moles of vinegar (acetic acid), then you know how many moles of vinegar you have.

You sure you don't need help?

 

[Tidus41390]

So all I need to do is convert my grams of vinegar to moles and I'll have my moles of sodium hydroxide...

Thanks guys.