• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Estimation of Iron 2 and Iron 3 in a mixture containing both

Extracts from this document...


The estimation of iron(II) and iron(III) in a mixture containing both Iron is a transition element. A transition element is an element that forms at least one ion with a partially file d orbital1. Transition metals have several different oxidation states, so can be oxidized and reduced. Oxidizing the Fe2+ will make it Fe3+, and it will lose an electron. Fe3+ e- + Fe3+ Reducing Fe3+ will bring it back to Fe2+, as it will gain an electron. Fe3+ + e- - Fe2+ I have been given a solution containing between 1.1g and 1.3g of iron ions, a mixture of Fe2+ and Fe3+. To work out how much Iron(II) and Iron(III) is in the mixture, I will start with a titration. I will determine the amount of Fe2+ in the mixture originally by titrating with potassium permanganate, and therefore oxidising the Fe2+ to Fe3+. Potassium permanganate, KMnO4, is self indicating, so when the oxidation point is reached, it changes brown. Then I will reduce the Fe3+ back to Fe2+ with zinc powder and work out the amount of Fe2+ in the remaining mixture by titrating the new mixture against approximately 0.1 molar potassium permanganate. ...read more.


Safe handling Wear safety glasses. Emergency Eye contact: Flush the eye with plenty of water. If irritation persists, call for medical help. Skin contact: Wash off powdered zinc with soap and water. If swallowed: Drink plenty of water and call for medical aid if the amount swallowed is substantial. Disposal Consult local rules. Note that powdered zinc may present a fire risk, so should not be disposed of in laboratory waste bins. Protective equipment Safety glasses may be suggested if you will be handling zinc powder. 4 Formula KMnO4 Physical properties Form: dark red to purple crystalline powder Stability: Stable, but decomposes if heated above 150 C. Melting point: ca 150 C (decomposes) Water solubility: moderate, produces solutions which are intensely coloured, even when quite dilute Specific gravity: 2.70 Principal hazards This material is harmful if swallowed or inhaled. It is also harmful if absorbed through the skin. Potassium permanganate is a strong oxidizing agent and may react very exothermically with organic materials. Safe handling Wear safety glasses and keep the solid or solution from contact with the skin.. ...read more.


of Fe2+ there will be, as the purple potassium permanganate will turn the solution colourless when it is all oxidised into Fe3+. After 3 concordant results of the Fe2+ being oxidised to Fe3+ with a certain amount of potassium permanganate, and the iron solution is now Fe3+, adding zinc powder will reduce it all back to Fe2+. A little bit is added sparingly until a colour change appears to brown. Zn + 2Fe3+ = Zn2+ + 2Fe3+ To find the total moles now, of Fe3+, I will titrate 25cm3 of the new solution of all Fe2+ with the approximate 0.1 molar potassium permanganate, the same I used in the first experiment. I will need to use more KMnO4 in the second titration as there is more Fe2+ to oxidise. All of the solution should turn colourless and be oxidised again to Fe3+. The amount of potassium permanganate used will be in proportion to the amount of Fe3+ in the 200cm3 solution. I will then calculate Moles of Fe2+ in second solution - Moles of Fe2+ in first solution = Moles of Fe2+ in complete solution. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Organic Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Organic Chemistry essays

  1. Determination of the formula of Hydrated Iron (II) Sulphate crystals

    + 5Fe2+(s) + 8H+ -> Mn2+(aq) + 5Fe3+(aq) + 4H2O(l) There are 5 Fe2+ ions to every one MnO4- ion in order to balance the number of electrons required by for each Mn2+ to form. The full ionic equation shows that to every 1 mole of MnO4- ions, there were 5 moles of Fe2+ ions.

  2. The aim of this experiment is to produce Aspirin. This is an estrification in ...

    - The meniscus may not have been on the graduation mark. To avoid these errors the following techniques were implemented:- - The solutions were added to the conical flask via pipettes. This delivered the specific volume accurately. - The solution made in the volumetric flask was mixed thoroughly and the

  1. investigating the amount of ascorbic acid present in fruit

    sample to the mg of vitamin C present in the titrated sample. To do this I will have to use this formula: Moles x Ar = mg of vitamin C in titrated sample So I will have to multiply the amount of moles of vitamin C in the orange, lime

  2. Comprehensive and Detailed Chemistry notes

    and halons in the atmosphere -- CFC's are haloalkanes where all hydrogen atoms are replaced by fluoro- and chloro- functional groups -- CFC's were developed in the 1930's replacing ammonia as refrigerants in refrigerators and air conditioners. -- CFC's were also used as proppelants in spray cans, solvents for cleaning

  1. Modern materials

    The overall arrangement of the molecules can be treated as a stack of nematic molecules twisting in a small angle for each layer. Normal liquid Nematic phase Smectic phase What is the function of liquid crystal in LCD? For a LCD to work, liquid crystals are packed between a polarizer

  2. Free essay

    Group II metals

    Any observations were recorded. Hydrochloric acid was added drop by drop to each of the three test tubes. After every drop, the test tubes were shaken in order to enable the solution to mix properly. The colour changes were recoded.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work