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OCR A Level Chemistry A – Module 2 Foundations in Chemistry

2.2.1
Electron Structure

Section 2.2.1 covers the electron shells, sub-shells and orbitals, the shapes of s and p orbitals, the filling rules and the electron configurations of atoms and ions up to krypton. One page covers the whole section.

Exam Paper
Paper 1 & 2
H432/01 and H432/02
Specification Points
2.2.1 (a) – (d)
4 learning outcomes
Sub-topics
1 lesson
Electron Configuration
Exam Board
OCR
H432 (2015 onwards)

Revision Notes

1 revision note, in the order the specification teaches them.

An s orbital beside three p orbitals
1

Electron Configuration

Shells, sub-shells and orbitals, s and p orbital shapes, filling order and the s p d configurations of atoms and ions up to Z = 36 (2.2.1 (a) to (d)).

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Electron Structure Map

OCR A Level Chemistry A · 2.2.1 Electron structure

The whole of 2.2.1 on one A4 page: orbitals and spin, s and p shapes, sub-shells, the filling order, configurations of atoms and ions, and blocks.

Download the map6 key ideas + a data table · A4 portrait · print ready

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Specification

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2.2.1

  1. a i

    the number of electrons that can fill the first shell

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  2. a ii

    the number of electrons that can fill the second shell

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  3. a iii

    the number of electrons that can fill the third shell

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  4. a iv

    the number of electrons that can fill the fourth shell

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  5. b (i)

    atomic orbitals as a region around the nucleus that can hold up to two electrons, with opposite spins

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  6. b (ii) a

    the shape of s-orbitals

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  7. b (ii) b

    the shape of p-orbitals

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  8. b (iii) a

    the number of orbitals making up s-sub-shells

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  9. b (iii) b

    the number of orbitals making up p-sub-shells

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  10. b (iii) c

    the number of orbitals making up d-sub-shells

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  11. b (iii) d

    the number of electrons that can fill s-sub-shells

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  12. b (iii) e

    the number of electrons that can fill p-sub-shells

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  13. b (iii) f

    the number of electrons that can fill d-sub-shells

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  14. c (i)

    filling of orbitals for the first three shells and the 4s and 4p orbitals in order of increasing energy

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  15. c (ii)

    filling of orbitals with the same energy, occupation singly before pairing

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  16. d (i)

    deduction of the electron configurations of atoms, given the atomic number, up to Z = 36

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  17. d (ii)

    deduction of the electron configurations of ions, given the atomic number and ionic charge, limited to s- and p-blocks up to Z = 36

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