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Edexcel International A Level Chemistry

Topic 2
Atomic Structure
& The Periodic Table

Topic 2 builds the foundation for atomic structure, isotopes, mass spectrometry, the quantum model, electronic configuration, ionisation energy and periodic trends. These ideas explain how evidence from spectra and ionisation energies supports modern models of electronic structure.

Exam Unit
Unit 1
WCH11/01 – IAS
Specification Points
2.1 – 2.18
18 points covered
Sub-topics
4 lessons
Revision notes available
Exam Board
Edexcel IAL
Pearson International

Revision Notes

4 revision notes, in the order the specification teaches them.

An atom with its nucleus and electron shells
1

Atomic Structure

Subatomic particles, relative mass and charge, atomic number, mass number, isotopes and particle calculations.

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A mass spectrometer with a stream of ions curving to a detector
2

Mass Spectrometry

Principles of a mass spectrometer, interpreting spectra, isotope abundance, relative atomic mass and diatomic mass spectra.

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An s orbital beside three p orbitals
3

Quantum Model

Orbitals, quantum shells, sub-shells, orbital box notation, electronic configuration and periodic blocks.

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An electron pulled clear of an atom
4

Ionisation Energy

First, second and third ionisation energies, successive ionisation energies, periodic trends and evidence for electronic structure.

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Summary Map

Download, print and revise the key facts of this topic at a glance.

Summary map

Download, print and revise the key facts of this topic at a glance.

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Summary map · PDF

Atoms and Mass Spectrometry Map

Edexcel International A Level Chemistry · Unit 1 · Topic 2A Atoms and Mass Spectrometry

The whole section on one A4 page: sub-atomic particles, isotopes, the mass spectrometer, relative atomic mass and the spectra of molecules.

Download the map6 key ideas + a data table · A4 portrait · print ready
Illustration of a summary map: compounds joined by reaction arrows
Summary map · PDF

Electronic Configuration Map

Edexcel International A Level Chemistry · Unit 1 · Topic 2B Electronic Configuration

The whole section on one A4 page: orbitals and spin, s and p shapes, sub-shells, the filling order, spdf and boxes, ions and blocks.

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

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Virtual Lessons

Recorded video lessons that teach the topic step by step.

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Virtual Lessons

Taught step by step in 5 recorded video lessons, to watch at your own pace.

Topic 2 Atomic Structure and The Periodic Table taught by a specialist chemistry teacher, in 5 recorded video lessons that follow the specification.

  • Learn it before you revise itEach lesson explains the chemistry step by step, with the diagrams, mechanisms and worked examples the exam expects.
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MCQ Bank

Multiple-choice papers on this topic, marked the moment you submit. MCQ (A) is free.

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Test yourself: 8 MCQ papers

Exam-style multiple-choice papers, marked the moment you submit with every answer explained. MCQ (A) is free.

8 exam-style multiple-choice papers, MCQ (A) to (H): 155 questions on Topic 2 Atomic Structure and The Periodic Table, written the way the exam asks them.

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SAQ Bank

Written, drawn and worked exam practice on this topic, marked by a specialist chemistry teacher.

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Written and drawn answers: 9 papers

Draw, write and calculate the way the exam asks, then a specialist chemistry teacher marks your work.

9 exam papers, (A) to (I): 133 questions on Topic 2 Atomic Structure and The Periodic Table with no multiple choice. You write explanations, work out calculations and draw answers: structures, mechanisms and diagrams.

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Specification

Every specification point in this topic, in the exam board's own words. Rate how confident you are with each one.

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2.1

  1. a

    know the structure of an atom in terms of electrons

    Revise
  2. b

    know the structure of an atom in terms of protons

    Revise
  3. c

    know the structure of an atom in terms of neutrons

    Revise

2.2

  1. a

    know the relative mass of protons

    Revise
  2. b

    know the relative charge of protons

    Revise
  3. c

    know the relative mass of neutrons

    Revise
  4. d

    know the relative charge of neutrons

    Revise
  5. e

    know the relative mass of electrons

    Revise
  6. f

    know the relative charge of electrons

    Revise

2.3

  1. a

    know what is meant by the term 'atomic (proton) number'

    Revise
  2. b

    know what is meant by the term 'mass number'

    Revise

2.4

  1. a

    be able to use atomic number and mass number to determine the number of electrons in an atom or ion

    Revise
  2. b

    be able to use atomic number and mass number to determine the number of protons in an atom or ion

    Revise
  3. c

    be able to use atomic number and mass number to determine the number of neutrons in an atom or ion

    Revise

2.5

  1. 2.5

    understand the term ‘isotope’

    Revise

2.6

  1. i a

    understand the basic principles of a mass spectrometer

    Revise
  2. i b

    be able to analyse and interpret mass spectra to: deduce the isotopic composition of a sample of an element

    Revise
  3. ii a

    understand the basic principles of a mass spectrometer

    Revise
  4. ii b

    be able to analyse and interpret mass spectra to: calculate the relative atomic mass of an element from relative abundances of isotopes and vice versa

    Revise
  5. iii a

    understand the basic principles of a mass spectrometer

    Revise
  6. iii b

    be able to analyse and interpret mass spectra to: determine the relative molecular mass of a molecule, and hence identify molecules in a sample

    Revise
  7. iv a

    understand the basic principles of a mass spectrometer

    Revise
  8. iv b

    be able to analyse and interpret mass spectra to: understand that ions in a mass spectrometer may have a 2+ charge

    Revise

2.7

  1. a

    be able to predict mass spectra for diatomic molecules, including chlorine, given isotopic abundances

    Revise
  2. b

    be able to predict relative peak heights for diatomic molecules, including chlorine, given isotopic abundances

    Revise

2.8

  1. a

    be able to define first ionisation energy

    Revise
  2. b

    be able to define second ionisation energy

    Revise
  3. c

    be able to define third ionisation energy

    Revise
  4. d

    understand that all ionisation energies are endothermic

    Revise

2.9

  1. 2.9

    know that an orbital is a region within an atom that can hold up to two electrons with opposite spins

    Revise

2.10

  1. a

    understand how ionisation energies are influenced by the number of protons in the nucleus

    Revise
  2. b

    understand how ionisation energies are influenced by electron shielding

    Revise
  3. c

    understand how ionisation energies are influenced by the sub-shell from which the electron is removed

    Revise

2.11

  1. i

    know that ideas about electronic structure developed from: an understanding that successive ionisation energies provide evidence for the existence of quantum shells and the group to which the element belongs

    Revise
  2. ii

    know that ideas about electronic structure developed from: an understanding that the first ionisation energy of successive elements provides evidence for electron sub-shells

    Revise

2.12

  1. a

    be able to describe the shape of an s orbital

    Revise
  2. b

    be able to describe the shape of a p orbital

    Revise

2.13

  1. i

    know that orbitals in sub-shells: each take a single electron before pairing up

    Revise
  2. ii

    know that orbitals in sub-shells: pair up with two electrons of opposite spin

    Revise

2.14

  1. a

    be able to predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive using s, p, d notation

    Revise
  2. b

    be able to predict the electronic configuration of ions of the elements from hydrogen to krypton inclusive using s, p, d notation

    Revise
  3. c

    be able to predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive using electron-in-boxes notation

    Revise
  4. d

    be able to predict the electronic configuration of ions of the elements from hydrogen to krypton inclusive using electron-in-boxes notation

    Revise

2.15

  1. 2.15

    understand that electronic configuration determines the chemical properties of an element

2.16

  1. a

    know that the Periodic Table is divided into blocks, such as s, p and d

  2. b

    know the number of electrons that can occupy s sub-shells in the first four quantum shells

    Revise
  3. c

    know the number of electrons that can occupy p sub-shells in the first four quantum shells

    Revise
  4. d

    know the number of electrons that can occupy d sub-shells in the first four quantum shells

    Revise

2.17

  1. a

    be able to represent data in graphical form for elements 1 to 36

    Revise
  2. b

    be able to use logarithms of first ionisation energies on a graph for elements 1 to 36

  3. c

    be able to explain the meaning of the term 'periodic property'

    Revise

2.18

  1. i

    be able to explain: the trends in melting and boiling temperatures of the elements of Periods 2 and 3 of the Periodic Table in terms of the structure of the element and the bonding between its atoms or molecules

    Revise
  2. ii

    be able to explain: the general increase and the specific trends in ionisation energy of the elements across Periods 2 and 3 of the Periodic Table

    Revise
  3. iii

    be able to explain: the decrease in first ionisation energy down a group

    Revise