ATAR Notes: Forum

VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: spudman on May 02, 2009, 01:53:32 pm

Title: Making Aspiring
Post by: spudman on May 02, 2009, 01:53:32 pm: Hi Guys,
2 weeks ago we did the prac from page 101 in the heinemann student workbook.
So, I'm wondering, does anyone actually know the chemical equation for the reaction of acetic anhydrite and salicylic acid?

Also, if we started with 3.00 g of salicylic acid, is it possible to end up with 5.68g of aspiring?

Thanks heaps guys..
Title: Re: Making Aspiring
Post by: TrueTears on May 02, 2009, 02:02:23 pm: The reaction to make Aspirin(acetylsalicyclic acid) is salicylic acid + Ethanoic anhydride $\to$ Aspirin(acetylsalicyclic acid) + ethanoic acid (acetic acid)

chemical equation is $C_7H_6O_3 + C_4H_6O_3 \to C_9H_8O_4 + C_2H_4O_2$
(salicylic acid) (Aspirin)
Title: Re: Making Aspiring
Post by: Toothpaste on May 02, 2009, 02:31:56 pm: Quote from: spudman on May 02, 2009, 01:53:32 pm
Also, if we started with 3.00 g of salicylic acid, is it possible to end up with 5.68g of aspiring?
Didn't dry it properly, probably. So yes, it's possible. Just remember to note this down when writing about errors. (The VCE way of making aspirin is actually flawed).
Title: Re: Making Aspiring
Post by: spudman on May 02, 2009, 02:44:59 pm: Another question:

How much do we need to know about "cracking" for VCE unit 3?
Title: Re: Making Aspiring
Post by: TrueTears on May 02, 2009, 02:58:03 pm: Cracking is just simply the breaking of larger molecules into smaller ones, shouldn't be too hard. I think it's mainly used around fractional distillation questions.
Title: Re: Making Aspiring
Post by: GoodGuys on May 06, 2009, 06:56:39 pm: how would we do a nice conclusion for this experiment?
Just sum everything up? and write way for improvements?
what would be good improvements?