This category covers the foundational concepts of redox reactions and oxidation numbers, including both classical definitions and electronic interpretations. Learn how to determine oxidation states and apply these concepts in chemical equations.
I (-1 in KI) becomes 0 in I₂, losing electrons; Cu (+2 to +1) is reduced.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
As (0 to +3 in As₂S₃): 2 As lose 6 electrons total. Per As = 6/2 = 3 electrons.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
Let Sb = x. F = -1. Equation: x + 5(-1) = 0, x - 5 = 0, x = +5.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
N (+5 in NaNO₃) to +3 in NaNO₂: 2 N gain 4 electrons total. Per NaNO₃ = 4/2 = 2.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
Let P = x. Cl = -1. Equation: x + 3(-1) = 0, x - 3 = 0, x = +3.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
In metal hydrides, H has an oxidation number of -1. For NaH: Na = +1, so +1 + x = 0, x = -1.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
S (+4 in SO₂) remains +4 in H₂SO₃. Change = 0 (not a redox reaction).
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
V (+3 in VCl₃) to +4 in VCl₄: change = +4 - (+3) = +1; each V loses 1 electron.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
C in CH₄: -4. In CHCl₃: x + 1 + 3(-1) = 0, x - 2 = 0, x = +2, which is higher.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
In superoxides, O has an oxidation number of -1/2. For KO₂: K = +1, so +1 + 2x = 0, 2x = -1, x = -1/2.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
N (0 in N₂) becomes -3 in NH₃. Change = -3 - 0 = -3.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
As (+3 in As₂S₃) to +5 in H₃AsO₄: change = +2. S (-2 in As₂S₃) to +6 in H₂SO₄: change = +8. S increases more.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
