Empirical and Molecular Formulae
Empirical and molecular formulae connect experimental composition data with the actual formula of a compound. These pages build from finding the simplest whole-number ratio of atoms through to using relative molecular mass to scale up to the true molecular formula.
These pages cover all four parts; the extra named ions, hydrated salts and limiting reagents follow with the supplementary set.
Revision Notes
2 revision notes, in the order the specification teaches them.
Empirical Formulae
Revise how to convert masses, percentages or combustion data into mole ratios and then into the simplest whole-number formula.
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Molecular Formulae
Learn how the empirical formula mass and relative molecular mass are used to find the molecular formula of a compound.
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Summary map
Download, print and revise the key facts of this topic at a glance.
Formulae and Hydrated Salts Map
Cambridge International AS & A Level Chemistry · Topic 2 Empirical formulae and hydrated salts
The whole section on one A4 page: empirical formulae from masses and percentages, molecular formulae, combustion analysis and hydrated salts.
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Revision Game
Match reagents to products, with your board's reagents and conditions.
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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.
Cambridge no longer issues a data booklet: the data you need are given in each question, and the syllabus has a Data section.
Self-assessment · 4 points
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