ATAR Notes: Forum

VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: dekoyl on February 24, 2009, 11:30:51 pm

Title: Analysing commercial Vitamin C tablets
Post by: dekoyl on February 24, 2009, 11:30:51 pm

When we buy Vitamin C tablets, it'll usually say something like "Brand Name - Vitamin C 500mg" and in fine print "Ascorbic Acid - 250mg and Sodium Ascorbate 281mg".
For a titration experiment, we're required to determine the amount of Vitamin C in the tablet. Do we compare the final figures with 250mg of Ascorbic Acid or the advertised 500mg of Vitamin C (I know Ascorbic acid is commonly known as Vitamin C).

I'm thinking to compare my experiment results against the 250mg of Ascorbic acid but for the sample pracs I've seen, they compare it with the whole 500mg. Which one should I do? :(


Thanks :)

Title: Re: Analysing commercial Vitamin C tablets
Post by: Mao on February 25, 2009, 12:14:09 am

Ascorbate is the conjugate base of Ascorbic acid, so you are not concerned about that. Compare it to the 250mg

Title: Re: Analysing commercial Vitamin C tablets
Post by: lacoste on March 04, 2009, 06:57:39 pm

Why do we use Iodine solution to titrate?

Does anyone have any background information about this prac? I'm confused as to if it is a redox titration or not?

any background info or pre-info appreciated .!