A Level Chemistry Data Booklet 2026 for H1, H2 and H3

The A Level Chemistry Data Booklet is issued by Cambridge Assessment International Education and is provided to students in all H1, H2 and H3 Chemistry papers, with the exception of practical examinations.

The booklet contains essential chemical data, including physical constants, ionisation energies, bond energies, standard electrode potentials, atomic and ionic radii, spectroscopic data, and the Periodic Table, that students are expected to reference and apply during their examinations, rather than memorise.

This page reproduces the full contents of the data booklet in a web-friendly format, with a clickable menu for quick navigation to each section. Reproduced for educational reference.

Contents: Tables of Chemical data

1. Important values, constants and standards

2. Ionisation energies (1st, 2nd, 3rd and 4th) of selected elements, in kJ mol⁻¹

3. Bond energies

4. Standard electrode potential and redox potentials, Eθ at 298 K (25 °C)

5. Atomic and ionic radii

6. Typical proton (¹H) chemical shift values (δ) relative to TMS = 0

7. Characteristic infra-red absorption frequencies for some selected bonds

8. The orientating effect of groups in aromatic substitution reactions

9. Qualitative Analysis Notes

10. The Periodic Table of Elements

1. Important values, constants and standards

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2. Ionisation energies (1st, 2nd, 3rd and 4th) of selected elements, in kJ mol⁻¹

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3. Bond energies

3(a) Bond energies in diatomic molecules (these are exact values)

3(b) Bond energies in polyatomic molecules (these are average values)

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4. Standard electrode potential and redox potentials, Eθ at 298 K (25 °C)

For ease of reference, two tabulations are given:
(a) an extended list in alphabetical order;
(b) a shorter list in decreasing order of magnitude, i.e. a redox series.

All ionic states refer to aqueous ions but other state symbols have been omitted.