Chapter 4 of 10
Revision Notes
d- and f-Block Elements — Revision Notes
ICSE · Class 12 · Chemistry
d- and f-Block Elements revision notes for ICSE Class 12 Chemistry: 4 topics in quick points. Part of the ICSE Class 12 Chemistry syllabus.
60 questions45 flashcards5 concepts
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Key Topics to Revise
1
1. Position, Definition, and Classification
- Transition elements are those in which the differentiating electron enters the (n-1)d subshell.
- They belong to groups 3 to 12 of the periodic table.
- The d-block lies between the s-block and p-block and shows intermediate behaviour between them.
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2. Electronic Configuration and Exceptional Cases
- Transition elements usually have electronic configuration of the type (n-1)d1-10 ns1-2.
- In the first transition series, electrons fill the 3d subshell from Sc to Zn.
- Cr has the exceptional configuration [Ar] 3d5 4s1.
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3. Atomic Size, Ionic Size, Density, and Metallic Nature
- Atomic radii in a transition series generally decrease with atomic number.
- The decrease becomes small after the middle of the series.
- Near the end of a series, atomic radii increase slightly due to increased electron-electron repulsion.
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4. Ionisation Enthalpy, Oxidation States, and Electrode Potentials
- Ionisation enthalpies of transition elements lie between those of s-block and p-block elements.
- The first ionisation enthalpy generally increases across a transition series, but not regularly.
- First ionisation enthalpies of the third transition series are higher than those of the first and second series.
Get complete notes with diagrams and examples
Full NotesKey Concepts
Transition elements are those elementsInner transition elements are thoseThe first transition series is ScChromium has [Ar] 3d5 4s1Zn
Frequently Asked Questions
What are the important topics in d- and f-Block Elements for ICSE Class 12 Chemistry?
Key topics in d- and f-Block Elements include Position, Definition, and Classification, Electronic Configuration and Exceptional Cases, Atomic Size, Ionic Size, Density, and Metallic Nature, Ionisation Enthalpy, Oxidation States, and Electrode Potentials. Study these first, then practise questions on each for the ICSE Class 12 board exam.
How should I revise d- and f-Block Elements for the ICSE Class 12 board exam?
Learn the core ideas first, then work through the 60 practice questions on d- and f-Block Elements. Revise definitions regularly and use flashcards for quick recall before the exam.
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Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.
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