Practical investigations
Read our general notes on Risk Assessment
I need to be able to carry out a volumetric procedure so that I can estimate the amount of iron(II) and iron(III) in a mixture containing both. I have looked at the recently asked questions and there is a similar one, however, this person seems to understand what they are doing - I don’t even know where to start! Please help.
Ulex writes
The starting-point is the reaction between iron(II) ions and potassium manganate(VII). This reaction is used in the analysis of iron tablets in experiment 19.1c, p 458 in the Nuffield Chemistry Students’ Book - I hope you’ve got access to this. You can adapt the method to find the amount of iron(II) in your mixture. The iron(III) present won’t be affected.
The next thing to do is to take a new sample of mixture and reduce all the iron in it to iron(II) using granulated zinc.
You then use your titration technique to find the total amount of iron in your mixture.
The amount of iron(III) can be found by subtracting the amount of iron(II) in the mixture from the total amount of iron as found in the second experiment.
Always carry out a risk assessment and check with your teacher before starting any practical work.
Risk assessment
Before attempting any practical work based on the advice and suggestions on this website, you must do the following. Identify any hazards, assess the risks from these hazards, and then decide appropriate control measures to reduce the risks. You must have these approved by those in authority in your school or college laboratory. Do not rely on what is said on this website.
For further guidance see our tutorial on Risk Assessment.
back to Practical investigations
Rate this page or react
Share your views on this page, 0 ratings so far
updated: 25 January 2006
