chap 8 Flashcards
involve a change in valence of reacting substances
• goes side-by-side, thus named as Redox
OXIDATION REDUCTION
gain of oxygen.
OXIDATION (in terms of oxygen transfer)
is loss of oxygen.
REDUCTION (in terms of oxygen transfer)
is loss of hydrogen.
REDUCTION (in terms of hydrogen transfer)
gain of hydrogen
REDUCTION (in terms of hydrogen transfer)
You would need to use an oxidising agent to remove the hydrogen from the ethanol.
A commonly used oxidising agent is
potassium dichromate(VI) solution acidified with dilute sulphuric acid.
is loss of electrons.
OXIDATION in terms of electron transfer)
gain of electrons
REDUCTION (in terms of electron transfer)
• substance that cause an increase in oxidation number
• used in the analysis of reducing agents
OXIDIZING AGENT
• Potassium Permanganate
• Potassium Dichromate
• Potassium Bromate
• Potassium Iodate
• Potassium Ferricyanide
• Ceric Sulfate
• FerricAmmonium Sulfate
• Iodine
• Bromine
Common Oxidizing Agents
the substance that cause a decrease in oxidation number
REDUCING AGENT
• Ferrous Ammonium Sulfate
• Sodium Thiosulfate
• Oxalic Acid
• Potassium Arsenite
• Titanium Chloride
• Ascorbic Acid
COMMON REDUCING AGENTS
Assay of Hydrogen Peroxide
- sample is titrated directly with KMnO4
DIRECT TITRATION
• Titration in which an excess standard KMnO4 solution is employed to oxidize a
substance and the amount in excess is determined by reduction with:
- excess standard oxalic acid
- excess ferrous ammonium sulfate and back titration with more standard KMnO4
RESIDUAL TITRATION
• Reaction is in acidic solution
• Standard permanganate is the titrant in direct and indirect method
• No indicator is required
PERMANGANOMETRY
