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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: whimsical create on November 17, 2019, 02:04:43 AM

Title: aspirin titration or back titration?
Post by: whimsical create on November 17, 2019, 02:04:43 AM: finding concentration of ASA in an aspirin ( how different temperature OR different prices of aspirins effect this - can't decide which would be more effective)

would I use titration or back titration?
Title: Re: aspirin titration or back titration?
Post by: Borek on November 17, 2019, 03:47:51 AM: What reactions are taking place during titration?
Title: Re: aspirin titration or back titration?
Post by: whimsical create on November 17, 2019, 10:31:54 AM: Quote from: Borek on November 17, 2019, 03:47:51 AM
What reactions are taking place during titration?

I will be dissolving a tablet into water (and maybe Ethyl alcohol if my teacher has it) and will be titrating it with NaOH to determine purity of aspirin.

For an IA I need 5 independent variables and was thinking about using different amounts of water+ethyl alcohol to help dissolve tablet. But I think the answer will be obvious if I increase the mL of the water+ethyl alcohol - the purity of aspirin will be less. So, if I use temperature will this be a good experiment? Would my results vary for each of the different temperatures?

Also, I mentioned that there is a possibility that my teacher does not have ethyl alcohol, can I use water instead?

Thank you.
Title: Re: aspirin titration or back titration?
Post by: Borek on November 17, 2019, 02:33:24 PM: You have not answered my question.
Title: Re: aspirin titration or back titration?
Post by: whimsical create on November 17, 2019, 03:31:48 PM: Quote from: Borek on November 17, 2019, 02:33:24 PM
You have not answered my question.

I know that in a back titration, it is used to easily and more quickly identify the endpoint than in the normal titration. It is used to determine the amount of unreacted reactant that was in excess. I want to find amount of ASA in tablet to determine purity of aspirin. I'm guessing back titration is used to be have more accurate calculations?

Did I answer your question?

Edit: I will perform a back titration. I now just need to think of five independent variables.
Title: Re: aspirin titration or back titration?
Post by: Borek on November 17, 2019, 05:42:21 PM: Come on, I didn't ask you to discuss differences between normal and back titration, I asked:

Quote from: Borek on November 17, 2019, 03:47:51 AM
What reactions are taking place during titration?
Title: Re: aspirin titration or back titration?
Post by: whimsical create on November 17, 2019, 07:21:39 PM: color change / pH change / neutralization
Title: Re: aspirin titration or back titration?
Post by: Borek on November 18, 2019, 03:43:16 AM: Actually there is another one. Technically aspirin is an ester. Do you know what happens to esters in water? Especially in pH far from neutral?