What does the quantitative and analysis part of Unit 1 cover?

It covers writing chemical formulae and balanced symbol and ionic equations, relative formula mass and the mole, reacting-mass and empirical-formula calculations, acids, bases, alkalis and the pH scale, neutralisation and the four reactions of acids, the methods for preparing soluble and insoluble salts, and the qualitative tests for metal ions, negative ions and gases.

What is the mole and why does it matter?

The mole is the chemist's counting unit: one mole of a substance has a mass in grams equal to its relative formula mass. It lets us count atoms by weighing, which is the link between the mass measured on a balance and the number of particles that react. The key equation is moles equals mass divided by relative formula mass.

How do I do a reacting-mass calculation?

Convert the known mass to moles using moles equals mass divided by relative formula mass, use the ratio in the balanced equation to find the moles of the substance you want, then convert back to mass using mass equals moles times relative formula mass. Always read the ratio from the big numbers in the balanced equation.

What salt does each acid make?

The salt ending comes from the acid: hydrochloric acid makes chlorides, sulfuric acid makes sulfates, and nitric acid makes nitrates. The metal part of the salt comes from the base. Acids react with metals to give a salt and hydrogen, with oxides and hydroxides to give a salt and water, and with carbonates to give a salt, water and carbon dioxide.

How should I revise the calculations and analysis topics?

Drill the mole calculations until they are automatic, always writing the equation and showing units. Learn the four reactions of acids and the salt-naming rule, and memorise the salt preparation methods. Learn the qualitative tests as a table of test, observation and conclusion, including flame colours, the sodium hydroxide precipitates, the anion tests and the four gas tests.

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CCEA GCSE Chemistry Unit 1: quantitative chemistry and analysis overview

A guide to the quantitative chemistry and analysis topics of CCEA GCSE Chemistry Unit 1. Covers writing and balancing equations, relative formula mass and the mole, reacting masses and empirical formulae, acids, bases and salts, salt preparation, and the qualitative tests for ions and gases.

Generated by Claude Opus 4.815 min readCCEAUpdated 2026-06-14

Reviewed by: AI editorial process; not yet individually human-reviewed

Jump to a section

Formulae and equations
The mole and calculations
Acids, bases and salts
Preparing salts and qualitative analysis
How the topics connect
How to revise this part of Unit 1
Sources

CCEA GCSE Chemistry Unit 1 is not only about structure; it is also where chemistry becomes quantitative and analytical. This guide gives an overview of how we count substances, write equations, make salts and identify ions and gases; the linked dot points work through each in exam depth.

Formulae and equations

Everything quantitative rests on correct formulae and balanced equations. Formulae are built by balancing ion charges so a compound is neutral. Equations are balanced by adjusting only the big coefficients, never the subscripts, because mass is conserved, atoms are only rearranged. State symbols (s, l, g, aq) show the physical states, and ionic equations strip a reaction down to the ions that actually change, such as $\text{H}^+ + \text{OH}^- \rightarrow \text{H}_2\text{O}$ for every neutralisation.

The mole and calculations

The mole is the heart of quantitative chemistry. One mole of a substance has a mass in grams equal to its relative formula mass, so the equation $\text{moles} = \dfrac{\text{mass}}{M_r}$ lets us count particles by weighing. From this single idea flow:

Reacting masses: convert to moles, use the equation ratio, convert back to mass.
Empirical formulae: turn masses or percentages into moles and find the simplest ratio.
Percentage composition: an element's share of the relative formula mass.

CCEA awards method marks for clear working, so always write the equation, substitute, and give units.

Acids, bases and salts

Acids produce hydrogen ions, alkalis produce hydroxide ions, and the pH scale measures how acidic or alkaline a solution is. Neutralisation makes a salt and water, and the salt's name comes from the acid (chloride, sulfate or nitrate) and the base (the metal). The four standard acid reactions, with metals, oxides, hydroxides and carbonates, are a frequent exam target, especially the carbonate reaction that also releases carbon dioxide.

Preparing salts and qualitative analysis

How you prepare a salt depends on its solubility. A soluble salt is made by adding excess insoluble base to acid, filtering off the excess and crystallising; an insoluble salt is made by precipitation, mixing two soluble solutions then filtering, washing and drying. Finally, qualitative analysis identifies what is present: flame tests and sodium hydroxide for metal ions, silver nitrate and barium chloride for halides and sulfates, acid for carbonates, and the four classic gas tests.

How the topics connect

These topics form the analytical toolkit of the subject. Correct formulae feed balanced equations; balanced equations feed mole calculations; mole calculations underpin both reacting masses and the concentration and titration work met later in Unit 2; and the salt and analysis topics put the equations to practical use in the lab. CCEA rewards students who can move from a balanced equation to a quantity and from an observation to an identification.

How to revise this part of Unit 1

Make the mole automatic. Practise moles, masses and relative formula masses until they are second nature.
Learn the acid reactions and salt naming as a small set of rules.
Memorise the preparation methods for soluble and insoluble salts.
Build a test table of every flame colour, precipitate and gas test with its conclusion.

Sources

CCEA GCSE Chemistry specification (1110), ccea.org.uk.