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lovewaffles
Dec 3, 2010, 07:07 AM
A sample of glycogen (10mg) was hydolysed in 2ml of 4M HCL. After neutralisation, the sample was diluted to 20ml. One ml of this soln was assayed, together with a series of standard glucose solutions. The Resulst were:

Glucose(ug/ml) Abs @ 620nm
0 0.035; 0.028
10 0.085; 0.091
30 0.186; 0.192
60 0.335; 0.342
90 0.480; 0.478
Sample(1ml) 0.275; 0.266

(I) Plot these data and establish a standard curve for glucose.
(ii) Determine the glucose concentration in the diluted sample.
(iii) Determine the glucose concentration in the original sample.
(iv) Was the hydrolysis complete?
(v) Given the molecular weight of glucose is 180, determine the molar concentration of a solution of 100ug/ml og glucose.

DrBob1
Dec 3, 2010, 09:15 AM
Almost, but not quite exactly, the same question was asked in August, 2007. Look it up and we'll go with Temp[lelane's answer for now. If you do have more questions ask for additional help.

lovewaffles
Dec 6, 2010, 08:49 AM
I have done out my standard curve, and I can make an attempt at the concentration for the Sample using its absorbency readings, but I am stuck at the calculations for the questions that follow and I have an exam on in a few days.

Unknown008
Dec 6, 2010, 09:25 AM
I have done out my standard curve, and I can make an attempt at the concentration for the Sample using its absorbency readings, but I am stuck at the calculations for the questions that follow and I have an exam on in a few days.

From your graph, find where the absorption is 0.275 and extrapolate to the standard curve, to get the concentration of the glucose.

I guess that you will be able to find the concentration of the original glucose, knowing that the previous solution was diluted to 20 mL.

Can you complete the rest now?