Special studies
You can find updated texts and experiments, study guides, web-links, and sample exam questions for Biochemistry, Materials Science, Chemical Engineering and Food Science. The new versions are easier to study while still covering everything needed for the Edexcel/Nuffield course. For Mineral Process Chemistry see the React tutorials and instructions about where to get the books.
In the Special Studies the experiments are not an optional extra but an integral part of the course.
Although the Edexcel Chemistry (Nuffield) specification does not expect you to be able to recall all the details of how to carry out the experiments, an exam question could describe the experiment to you, and then ask for an understanding of why it was conducted in the manner described or to give an outline of the results expected. The best way to prepare for this is to do the experiments!
Recently Asked Questions
- I have to determine the amount of urea in urine for a biochemistry investigation. Equation: Urea + water + urease enzyme -> ammonium carbonate In a method for making a calibration curve which I got from a book, it says to add the 2 cm3 x% solution of urea to 50 cm3 of 4% solution of urease (enzyme) and leave in a waterbath maintained at 35 oC for an hour. I carried out a preliminary investigation, but my school only allowed me to use 10 cm3 5% urease (enzyme) solution to 2 cm3 x% urea solution. As the pH of ammonium carbonate is approximate, I used universal indicator to see when the reaction was completed. I found it was completed within 10 minutes, which is a pretty small value compared with one hour. Do you have an ideas why the method states 1 hour? Am I missing something fairly obvious? 020608
- Hi, my experiment is on the effect of different cooking methods on the vitamin C content in capsicums. I used the titrimetric method involving the redox reaction between ascorbic acid and DCPIP. Through calculations I found that the concentration of ascorbic acid (397 mg/100 g) was way higher than the literature values (191 mg/100 g). Why is this so? I found that microwaving was the best method at retaining vitamin C, followed by steaming and boiling. Can you suggest detailed chemical reasons as to why microwaving is a better method as compared to steaming and boiling, and why steaming is better than boiling? Also when titrating DCPIP with a standard solution of ascorbic acid, I am often unable to obtain the pink end-point. The initially colourless solution usually turns to a very light yellowish-brown colour. Could this be the end-point? 130408
- I have been looking at the RSC method of analysis of paracetamol (titration with ammonium cerium(IV) sulfate). It says to "repeat the operation without the test material being present. The difference between the titration figures represents the amount of ammonium cerium(IV) sulfate required." What does this actually mean and why do I need to know the amount of ammonium cerium(IV) sulfate? Am I testing the paracetamol I have made or a known tablet form? 260308
updated: 18 December 2007
