Chemistry · Class 12 · Chapter 4
The d- and f-Block Elements
13 lessons 97 min 2 simulations
The d-block fills the wide middle of the periodic table (groups 3-12) and the f-block sits in two rows below it. The chapter explains why these metals are hard, high-melting and similar across a row, why their ionisation enthalpies and electrode potentials run irregularly, and how partly filled d orbitals give them many oxidation states, paramagnetism, colour, complexes and catalytic power. It then studies two workhorse oxidants, K₂Cr₂O₇ and KMnO₄, and closes with the lanthanoids (and the lanthanoid contraction) and the actinoids.
What the exam asks
NEET asks for configurations of atoms and ions (Cr, Cu and ions that lose 4s first), which elements are not transition elements, spin-only magnetic moments, the colour of aquated ions, the reasons behind anomalies (Mn and Zn E°, Cu's positive E°, Mn³⁺ oxidising, Cr²⁺ reducing), balanced equations for dichromate and permanganate, and the lanthanoid contraction with its Zr-Hf consequence. Marks go on removing 3d electrons before 4s, calling Zn a transition element, forgetting that Ce⁴⁺ is an oxidant and Eu²⁺ a reductant, and mixing up the electrons accepted by MnO₄⁻ in acidic and neutral media.
Lessons
13 lessons · 97 min
1Position and electronic configurationNCERT §4.1; §4.26 min2Physical properties and atomic sizeNCERT §4.3.1; §4.3.27 min3Ionisation enthalpiesNCERT §4.3.36 min4Oxidation statesNCERT §4.3.46 min5Electrode potentialsNCERT §4.3.5; §4.3.66 min6Higher oxidation states and reactivityNCERT §4.3.7; §4.3.86 min7Magnetic propertiesNCERT §4.3.910 min 1 sim8Coloured ions and complexesNCERT §4.3.10; §4.3.116 min9Catalysts, interstitial compounds and alloysNCERT §4.3.12; §4.3.13; §4.3.146 min10Potassium dichromate and permanganateNCERT §4.4; §4.4.111 min 1 sim11The lanthanoidsNCERT §4.56 min12The actinoids and applicationsNCERT §4.6; §4.76 min13Chapter reviewMust-know facts, traps and formulas15 min