37 public questions tagged with this topic.
Fe₂+ (d6), weak field H₂O, octahedral, high spin: t2g4 eg2. Ratio = 2 : 4 = 1 : 2.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Werner's Theory and Definitions - Ligands Coordination Number
Fe₃+ (d5) high spin: t2g3 eg2, so 2 electrons in eg.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Nomenclature of Coordination Compounds
Cr₃+ (d3) in [Cr(NH₃)6]3+ (octahedral) with moderate field NH₃ has t2g3, so 3 electrons.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Geometrical Isomerism in Coordination Compounds
Mn 2+ has 5 unpaired electrons (3d 5 ), the maximum in the 3d series.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Applications of d and f Block Elements
In BH₃ , boron has 3 bonds (6 electrons), resulting in an incomplete octet due to only 3 valence electrons.
Ref: NCERT Class 11 Chemistry > Chapter 4: Chemical Bonding and Molecular Structure > Topic: Kossel-Lewis Approach and Octet Rule and Lewis Structures
For B₂ : (sigma 1s)² (sigma^* 1s)² (sigma 2s)² (sigma^* 2s)² (pi 2px)¹ (pi 2py)¹ , with two unpaired electrons, making it paramagnetic.
Ref: NCERT Class 11 Chemistry > Chapter 4: Chemical Bonding and Molecular Structure > Topic: Ionic Bonding - Lattice Enthalpy and Properties of Ionic Compounds
Chlorine (Cl) has 7 valence electrons ( [Ne] 3s² 3p⁵ ). Gaining one electron forms Cl⁻ with a noble gas configuration ( [Ar] ).
Ref: NCERT Class 11 Chemistry > Chapter 4: Chemical Bonding and Molecular Structure > Topic: Hydrogen Bonding and Resonance and Dipole Moment
The fifth period (n=5) includes 5s (2 electrons), 4d (10 electrons), and 5p (6 electrons), totaling 18 electrons.
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Nomenclature of Elements with Atomic Number >100
Total electrons = 17, corresponding to Cl (period 3, group 17). Others: S (16 electrons), Ar (18 electrons), P (15 electrons).
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Electronic Configuration and Types of Elements - s p d f Blocks
For isoelectronic species (36 electrons), radius increases with decreasing nuclear charge. Br⁻ (Z=35) has the largest radius compared to K+, Ca²⁺, or Sc³⁺.
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Electronic Configuration and Types of Elements - s p d f Blocks
This configuration (Z=31) corresponds to Ga (period 4, group 13), with 4p¹ distinguishing it from Zn (4p⁰), Ge (4p²), or As (4p³).
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Anomalous Properties and Second Period and Chemical Reactivity
For l=2 (d), orbitals = 5. Electrons = 10.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Shapes of Orbitals - s p d f and Nodes and Radial Probability
