🧪

Overview of AQA Chemistry Paper 2 Topics

May 27, 2025

View transcript

AQA Chemistry Paper 2 Overview

Topics Covered

  • Rates of Reaction
  • Organic Chemistry
  • Chemical Analysis
  • Atmospheric Chemistry
  • Using Resources

Rates of Reaction (Topic 6)

  • Definition: Speed at which a reaction happens.
  • Rate Formula: Change in quantity/time.
  • Measurement: Quantity could be mass or gas volume.
  • Experiments:
    • Hydrochloric acid and sodium thiosulfate: Increased turbidity (cloudiness).
    • Gas production experiment using a gas syringe.
  • Graph Interpretation:
    • Plot with quantity on y-axis and time on x-axis.
    • Curve starts steep and plateaus.
    • Draw tangent for rate at any time.
  • Factors Increasing Rate:
    • Increase concentration, pressure, surface area.
    • Temperature increase leads to more frequent, energetic collisions.
    • Catalysts reduce activation energy.

Reversible Reactions and Equilibrium

  • Dynamic Equilibrium: Rates of forward and reverse reactions equal.
  • Le Chatelier’s Principle: System adjusts to counteract changes.
  • Pressure and Temperature Effects:
    • Increase pressure favors side with fewer moles.
    • Temperature increase favors endothermic reaction.

Organic Chemistry (Topic 7)

  • Crude Oil:
    • Contains hydrocarbons, primarily alkanes.
    • Fractional distillation separates alkanes by boiling point.
  • Alkanes & Alkenes:
    • Alkanes: Single bonded, saturated hydrocarbons.
    • Alkenes: Double bonded, unsaturated, reactive.
  • Cracking: Converts long alkanes to shorter alkanes and alkenes.
  • Polymers:
    • Made from alkenes (addition polymerization).
    • Condensation polymerization forms polyesters.

Chemical Analysis (Topic 8)

  • Purity and Formulations: Specific melting/boiling points; designed mixtures.
  • Chromatography: Separates substances, calculates Rf values.
  • Tests for Gases:
    • Hydrogen: Squeaky pop.
    • Oxygen: Relights glowing splint.
    • Carbon Dioxide: Turns limewater cloudy.
    • Chlorine: Bleaches damp litmus paper.
  • Flame Tests and Metal Ions:
    • Specific colors for metal ions.
    • Precipitation reactions with NaOH.

Atmospheric Chemistry

  • Historical Changes: Composition started with nitrogen and CO2.
  • Greenhouse Gases: CO2, methane, water vapor.
  • Environmental Impact:
    • Carbon footprint awareness.
    • Atmospheric pollutants and effects.

Using Resources (Topic 10)

  • Sustainability: Meeting current demands without compromising future needs.
  • Water Treatment:
    • Potable water: Low salt and microbes.
    • Desalination for sea water.
  • Metal Extraction: Phytomining and bioleaching for copper.
  • Life Cycle Assessments (LCA): Evaluates environmental impact.
  • Corrosion and Protection: Methods to prevent metal degradation.
  • Alloys: Mixtures of metals to enhance properties.
  • Glass and Ceramics: Different types and uses.
  • Polymers:
    • Thermosoftening vs. Thermosetting.
  • Haber Process:
    • Ammonia production for fertilizers.
    • Conditions for optimal production.
  • Fertilizers: Importance of nitrogen, phosphorus, potassium.

These notes provide a concise summary of key concepts and experiments related to these topics, helping to prepare for the AQA Chemistry Paper 2 exam. Good luck studying!

Full transcript