What does Unit C1 cover in CCEA Double Award Science?

Unit C1, Structures, Trends, Chemical Reactions, Quantitative Chemistry and Analysis, covers atomic structure and isotopes, the Periodic Table and electron arrangement, the groups and their trends, ionic, covalent and metallic bonding, elements, compounds, mixtures and separation, symbols, formulae, equations and the mole, acids, bases and salts, and tests for ions and gases.

How is Unit C1 assessed in the Double Award?

C1 is one of the externally marked written units of the GCSE Science Double Award (code 1370). It is sat at either Foundation or Higher tier and uses structured short-answer questions, data and calculation questions, and longer questions. With the other five written units and the Practical Skills unit it makes up the two GCSE grades of the Double Award.

What calculations come up in Unit C1?

The main calculations are relative atomic mass from isotopic abundances, relative formula mass, the mole (moles equal mass divided by relative formula mass), balancing equations, and reacting-mass calculations using the equation ratio. A calculator is allowed in the written papers.

Which practicals are linked to Unit C1?

Prescribed practicals linked to C1 include separation techniques such as filtration, crystallisation, distillation and chromatography, preparing a soluble salt, flame tests and tests for ions, and tests for gases. These feed into the Practical Skills unit.

How should I revise Unit C1?

Master electron arrangement first, because it explains the Periodic Table and bonding. Learn the bonding-to-properties links, drill balancing and the mole calculations until they are automatic, and memorise the salt-preparation method and the ion and gas tests. Then practise CCEA past-paper questions and the calculations.

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CCEA GCSE Double Award Science: C1 Structures, Trends, Reactions and Analysis overview

An overview of Chemistry Unit C1 (Structures, Trends, Chemical Reactions, Quantitative Chemistry and Analysis) of CCEA GCSE Double Award Science, mapping atomic structure, the Periodic Table, bonding, the mole, acids and salts, and tests for ions and gases.

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What this unit covers
How it is examined
How to study it

Unit C1 of CCEA GCSE Double Award Science is the first Chemistry unit. It builds from the atom up to chemical reactions and laboratory analysis, and is examined on the C1 written paper at Foundation or Higher tier. This page maps the topics and links to a focused answer page for each one.

What this unit covers

Atomic structure and isotopes: Protons, neutrons and electrons, atomic and mass number, isotopes, and relative atomic mass. See Atomic structure and isotopes.
The Periodic Table and electron arrangement: Electron shells, the link to group and reactivity, and the organisation into periods and groups. See The Periodic Table and electron arrangement.
Groups and trends: The alkali metals, the halogens with displacement, and the noble gases, linked to electron arrangement. See Groups and trends.
Bonding: ionic, covalent and metallic: The three bonding types, dot-and-cross diagrams, and how structure explains properties. See Bonding: ionic, covalent and metallic.
Elements, compounds, mixtures and separation: The definitions, physical and chemical change, and separation techniques. See Elements, compounds, mixtures and separation.
Symbols, formulae, equations and the mole: Writing formulae and balanced equations, relative formula mass, the mole, and reacting masses. See Symbols, formulae, equations and the mole.
Acids, bases, salts and reacting masses: The pH scale, neutralisation, the four reactions of acids, and preparing salts. See Acids, bases, salts and reacting masses.
Tests for ions and gases: Flame tests, sodium hydroxide tests, tests for negative ions, and the gas tests. See Tests for ions and gases.

How it is examined

C1 is one written unit of the Double Award, sat at the same tier as the other units. Expect structured questions on atomic structure, electron arrangement, bonding and properties, balancing equations, mole calculations, acids and salts, and the laboratory tests. A calculator is allowed.

How to study it

Master electron arrangement first, because it explains the Periodic Table, the group trends and bonding. Learn the structure-to-properties links, drill balancing and the mole calculations, and memorise the salt-preparation method and the ion and gas tests. Then practise CCEA past papers and finish with the module quiz.

Sources & how we know this

CCEA GCSE Science Double Award specification — CCEA (2017)