[Shaftell]

Hello everyone.

I'm doing my lab and I am having difficulty calculating the % of acetic acid (by mass).

The question says using the provided molarity(0.298M) of the NaOH solution, calculate the % of acetic acid (by mass) in each sample. Note: the total mass of each 25.00 ml sample is given by total mass=density x volume. Assume the density of the acetic acid solution is 1.000g/ml.

So I took the molarity and used the volumes I had from my lab, as well as the balanced equation to get it into grams of acetic acid. But now I'm stuck because I have no idea what to do next in terms of finding the % mass.

Thanks, any help would be appreciated!

[Hunter2]

You calculate the amount of you acetic acid by titration. With the molar mass of acetic acid you can convert to the mass. The given mass was 25 g because density was 1,000 g/ml.
The ratio times 100% is your percentage.

[Shaftell]

Thanks for replying. Sorry I didn't quite understand that.

What I've done so far is grabbed the 0.2980Mx0.2190L (the volume that I used in titration).

Then I took the 0.06526 mols of NaOH and used  the conversion factors to get 3.917g of acetic acid. This is where I'm stuck because I don't know what I'm suppose to do with this number and the density number that was given to me. And how to use all of that to get the mass%.

Thanks again for replying.

[Hunter2]

You reached almost destination. Divide your mass by 25 and multiply by 100% is your Percentage. In your example 15,7%

[Shaftell]

Okay that is the way I was heading but I wasn't sure. Thank you so much!