Transition Metals and Coordination Compounds- Reduction of Permanganate Ion by Sulfide Ion

Chloro Complexes of Cobalt (II)

Color Fan

Oxidation States of Vanadium

Precipitates and Complexes of Nickel (II)

Precipitates and Complexes of Silver (I)

Formation of a Silver Mirror

Spectroscopy for Large Lecture Hall II

Bromo Complexes of Copper (II)

Colorful Complex Ions in Ammonia

Colors of Complexes of Transition Metal

Hydration of Cu (II) Ion

Iron (III) Thiocyanate Complex Ion Equilibrium

Precipitates and Complexes of Copper (II)

Precipitates and Complexes of Iron (III)

Relationship of Absorbed Light to Observed Color

Samples of Minerals

The Copper Mirror

Reduction of Permanganate Ion by Sulfide Ion

Slow Formation of Chloro Complex of Chromium (III) Ion

 Reduction of Permanganate Ion by Sulfite Ion. 

Description:  A sample of potassium permanganate is placed in a Petri dish and treated with aqueous hydrochloric acid. Then sodium sulfite solution is added to the mixture. The clear and deep purple solution changes to clear pale pink as the permanganate is reduced from Mn(VII) to Mn(II) during the course of the reaction.  

    H+ 

4KMnO4(aq) + 5Na2S2O3(aq) + 9H2O(l)(aq) → 4MnSO4 +10Na+(aq) + 6SO4-2(aq) + 4K+(aq) + 2Cl–(aq) 

2 KMnO4 + 16 HCl + 10 Na2S2O3 → 2 MnCl2 + 5 Na2S4O6 + 10 NaCl + 2 KCl + 8 H2O 

Mn(VII) +5e– → Mn(II) 

S(II) – 4e– → S(VI) 

Source: UW-Madison Card Catalog

Year: N/A  Vol:  N/A    Page: N/A

Keywords: Reduction, Permanganate, Sulfate, Sulfite, Oxidation, Acid catalysis 

Rating:

Hazards: Some

• Acute toxicity hazard- oral
• Skin corrosion hazard
• Corrosive to metals
• Serious eye damage
• Long-term (chronic) aquatic toxicity hazard
• Short-term (acute) aquatic toxicity hazard
• Oxidizing solids
• Specific target organ toxicity- respiratory hazard, brain
• Electric shock hazard

Effectiveness: Good

• Results are observable without guidance
• Good connection from demo to course material
• Contrast in systems behavior is clear
• Time to results is low
• Good reliability

Difficulty: Low

• Simple manipulations for most to perform
• Demos at standard conditions
• Simple procedures
• Use of mildly reactive substances

Safety Precautions:

• Eye protection required
• Gloves required
• Avoid exposure to mists, droplets, dusts, or vapors
• Perform in a well-ventilated area
• Use UL approved three-prong plug and outlet

Class: Redox Reactions, Transition Metals and Coordination Compounds

Division: Inorganic Chemistry , General Chemistry Divisions

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