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Combined Science
OCR GCSE Combined Science A
Chemical Reactions
Introduction to Chemical Reactions

OCR GCSE Combined Science A · J250

Introduction to Chemical Reactions

Recall chemical symbols and formulae for elements and compounds.
Represent chemical reactions accurately using the appropriate chemical formulae and balanced equations.
Understand the principles of conservation of mass, physical changes of state, and foundational chemical reaction types.

Subtopics

1
Formulae of Elements and Compounds
2
Writing Chemical and Half Equations
3
Using the Periodic Table for Formulae
4
Deducing Compound Formulae from Ions
5
Balanced Ionic Equations
6
Using State Symbols
7
Gas Identification Tests
8
The Avogadro Constant and the Mole
9
Mass and Moles Relationship
10
Solution Concentration
11
Conservation of Mass
12
Mass Changes in Non-Enclosed Systems
13
Equation Stoichiometry and Limiting Reactants
14
Calculating Reactant and Product Masses

14 of 14 subtopics have revision notes available.

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