Redox Reaction Flashcards
What is the Redox Reaction?
Reduction + Oxidation
What is the meaning of Oxidation Number?
Charge present on an atom in a chemical unit
Oxidation of free molecules or atoms, and naturally occurring chemical units will be always
0
Oxidation Number of ions
Charge present on ions
O.N. of alkali metals
+1
O.N. of alkaline earth metals
+2
O.N. of aluminum
+3
O.N. of oxygen
-2
O.N. of flourine
-1
Oxidation
Adding an electronegative element
Increase in oxidation number
Loss of electron
Reduction
Adding an electropositive element
Decrease in oxidation number
Gain of electron
Oxidising Agent
Agent which oxidises other and reduces itself
Reducing Agent
Agent which reduces other and oxidises itself
Normality
No. of gram equivalent of solute/ volume of solution in litres
N-factor of an acid
Removal of protons, valency factor
N-factor of a base
Acidity, Removal of -OH ion
N-factor of a salt
Total +ve or -ve charge present in the salt
N-factor of oxidising and reducing agent
Change in oxidation number per molecule
O.N. of KMnO4 in all three medium
Acidic-5
Basic - 1
Neutral - 3
Disproportionation Reaction
Reaction in which oxidation and reduction takes place in the same compound
Comproportionate Reaction
Reverse of disproportionate reaction
Indicators
Weak organic acids or weak organic bases which indicate the end point of a reaction
Phenolphthalein
Weak organic acid has a pH range of 8.3 to 10.5
Colour that Phenolphthalein changes to in acidic and basic medium
Colourless and Light Pink
Methyl Orange
Weak organic base having a pH range of 3.1 to 4.4
Colour that Methyl Orange changes to in acidic and basic medium
Yellow and Red
Hard Water and Soft Water
Water which cannot form foam and water which can form foam
Temporary and Permanent Hardness is due to
Temporary - Due to bicarbonates of calcium and magnesium
Permanent - Due to chlorides and sulphates of calcium and magnesium
Methods to remove temporary hardness
Boiling, Clerks Method, Treatment with washing soda
Methods to remove permanent hardness
Ion-Exchange method, Resins
