AQA GCSE Chemistry Paper 1 Revision Notes

Introduction

• Covers topics relevant for Higher, Foundation Tier Double Combined Trilogy, and Triple Separate Chemistry.
• Topics include Atoms, Bonding, Quantitative Chemistry, Chemical, and Energy Changes.

Basic Concepts

• Atoms and Elements: Represented by symbols in the periodic table.
• Compounds: Formed from two or more types of atoms chemically bonded, e.g., H2O.

Chemical Reactions

• Balancing Equations: Essential as atoms are not created or destroyed.
  • Start with compounds, e.g., balancing hydrogen and oxygen in water.
• Mixtures: Combination of elements/compounds not chemically bonded, e.g., air.
• Separation Techniques:
  • Filtration, Crystallization, Distillation, and Fractional Distillation.

States of Matter

• Solid, Liquid, Gas: Different states based on particle arrangement and energy.
• Physical Changes: Changes in state are physical, not chemical reactions.

Atomic Models and Structure

• Development of Atomic Theory:
  • J.J. Thompson, Ernest Rutherford, Niels Bohr, James Chadwick.
• Subatomic Particles:
  • Protons (+1), Neutrons (0), Electrons (-1).
• Periodic Table:
  • Atomic number (protons), Mass number (protons + neutrons).
  • Isotopes: Variants with different neutrons.

Electron Configuration

• Electrons arranged in shells, described by configuration (e.g., Mg: 2,8,2).
• Metals vs. Non-metals based on electron donation/acceptance.

Groups in the Periodic Table

• Group 1 (Alkali Metals): Reactivity increases down the group.
• Group 7 (Halogens): Reactivity decreases down the group.
• Group 0/8 (Noble Gases): Unreactive due to full outer shells.

Ions and Ionic Compounds

• Formation: Metals lose electrons, non-metals gain electrons.
• Ionic Bonding: Formation of compounds with high melting points.

Covalent Bonding

• Single, Double, Triple Bonds: Sharing electrons between non-metals.
• Molecular Structures: Simple (low boiling points) vs. Giant (e.g., diamond).

Quantitative Chemistry

• Mass Conservation: Mass of reactants equals mass of products.
• Moles and Calculations:
  • Moles = Grams/RAM (Relative Atomic Mass).
  • Stoichiometry and balancing in reactions.

Reactivity Series and Chemical Changes

• Reactivity Series: Determines reactions, e.g., displacement.
• Redox Reactions:
  • Oxidation is loss, reduction is gain (OIL RIG).

Acids, Bases and Salts

• Neutralization: Acid + Alkali = Salt + Water.
• Titrations: Used to find concentration, involves indicators.

Electrolysis

• Process: Separation of substances using electrical current.
• Uses: Metal extraction, purification.

Energy Changes in Reactions

• Exothermic and Endothermic: Based on energy release or absorption.
• Energy Profiles: Diagrams showing energy changes.

Additional Topics (Triple Only)

• Atom Economy: Efficiency of mass in chemical reactions.
• Fuel Cells and Batteries: Operation and energy production.

Conclusion

• Review of all topics, encourage further study and practice for exams.