Dear Kennedy,

The attached pdf file describes in details the theoretical and experimental parts of the reduction of hexacyanoferrate by ascorbic acid (Vitamin C). I have copied the first paragraphs from the publication for quick view.

 THE OXIDATION OF ASCORBIC ACID

BY HEXACYANOFERRATE(III) ION

The Effect of Sodium Nitrate on the Reaction Rate2

I. PURPOSE OF THE EXPERIMENT

This is an integrated experiment that includes topics from inorganic, organic, analytical,

physical, and computational chemistry. It is designed to introduce you to the basics of:

• how to acquire experimental kinetic data for a chemical reaction;

• how to perform data manipulation in order to extract information such as reaction order

and rate constants from experimental kinetic data;

• how to assess the effect of the reaction environment upon rate constant. In the present

case, how adding a salt modifies the environment.

Pieced together, correct information will elucidate the reaction mechanism. Also, the numerical

results allow a convincing check of the validity of the mechanistic assumptions.

This experiment will contribute to improving your lab technique in the following areas:

• precise volumetric and gravimetric measurements

• correct handling of the UV-VIS instrument

• use Microsoft Excel Solver (see Appendix 3) that provides the graphical and numerical

output resulting from your experimental data.

II. SAFETY

1. Ascorbic acid (Vitamin C): Pleasant, sharp acidic taste. Stable in air when dry. Aqueous

solutions are rapidly oxidized by air. Alkalies, iron, and copper accelerate the reaction. Used as

antimicrobial and antioxidant in foodstuffs. Not considered toxic except in immense quantities. 

2. Potassium Hexacyanoferrate (III): The aqueous solution decomposes on standing. Avoid

contact with acid. Harmful solid. NOTE: cyanide (CN–

) ions are highly toxic but are tightly

bound to the iron nucleus in this compound and so are not available in solution. (This is what

happens when cyanide gets into your blood: it binds to the iron centers in hemoglobin making it

impossible for red blood cells to carry oxygen to the organism, thus killing by asphyxiation.) But

when hexacyanoferrate decomposes or hydrolyzes to release free CN–

, it forms a lethal poison.

3. Nitric Acid: Irritant, toxic, avoid eye contact, harmful if inhaled, causes severe burn. May

be fatal if swallowed or ingested. Strong oxidizer. Contact with other materials may cause fire.

4. EDTA: Harmful solid, irritant.

5. Sodium Nitrate: Avoid eye contact, ingestion. Strong oxidizer, toxic, irritant. Target

organs: Blood and nerves.

Hoping this will be helpful,

Rafik

Thank you.nice one