7 public questions tagged with this topic.
In [Mn(CN)6]4−, each CN− is −1, totaling −6 for 6 ligands. The overall charge is −4. Thus, x + (−6) = −4, so x = +2.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
KMnO 4 has Mn in +7 oxidation state (highest oxidation state for Mn).
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: General Properties of d-Block - Electronic Configuration and Trends
E°cell = 0.85 - (-1.18) = 2.03 V . Ecell = 2.03 - (0.059/2) log (0.005/0.02) = 2.03 + 0.02065 = 2.05065 V .
Ref: NCERT Class 12 Chemistry > Chapter 2: Electrochemistry > Topic: Electrochemical Cells - Galvanic Cells and Electrode Potential
Mn (+4 in MnO₂) becomes +6 in K₂MnO₄. Change = +6 - (+4) = 2 electrons per Mn.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Electrode Potential and Electrochemical Series and Galvanic Cells
Let Mn = x. O = -2. Equation: x + 2(-2) = 0, x - 4 = 0, x = +4.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Balancing Redox Reactions - Oxidation Number Method and Half Reaction
H (+1 in KOH) becomes 0 in H₂, gaining electrons.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Applications of Redox Reactions and Disproportionation
In period 4 d-block (Sc to Zn), Mn (group 7) achieves a +7 oxidation state in Mn₂O₇, unlike Cr (+6), Fe (+3), or Co (+3).
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Anomalous Properties and Second Period and Chemical Reactivity
