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Chemical reactions

Revision and exam practice for Chemical reactions.

34

Objectives

10

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10

Questions

90 min

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OcrGcseCombined Science A GatewayChemical reactions

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34 objective pages available

Writing Chemical Formulae for Elements and Compounds1 objectives
  • Apply chemical symbols to write the formulae of elements and simple covalent and ionic compounds.
Conservation of Mass in Chemical Reactions1 objectives
  • Apply the names and symbols of common elements and compounds and the principle of conservation of mass to write formulae and balanced chemical equations and half equations.
Understanding Chemical Formulas and Equations with the Periodic Table1 objectives
  • Apply the names and symbols of common elements from a supplied Periodic Table to write formulae and balanced chemical equations where appropriate.
Deducing Chemical Formulas from Ion Charges1 objectives
  • Apply the formula of common ions to deduce the formula of a compound.
Producing Balanced Ionic Equations (Higher Tier)1 objectives
  • Produce balanced ionic equations.
Understanding State Symbols in Chemical Equations1 objectives
  • Communicate the key features of the physical states of products and reactants using state symbols (s, l, g and aq).
Identifying Common Gases: Tests and Observations1 objectives
  • Communicate the key features of tests to identify selected gases.
Understanding the Mole and Avogadro Constant (Higher Tier)1 objectives
  • Retrieve and apply knowledge of and use the definitions of the Avogadro constant (in standard form) and of the mole.
Moles, Mass, and Molar Mass (Higher)1 objectives
  • Account for the way the mass of a given substance is related to the amount of that substance in moles and vice versa.
Understanding Solution Concentration: Mass, Volume, and Calculations (Higher Tier)1 objectives
  • Account for the way the mass of a solute and the volume of the solution is related to the concentration of the solution.
Understanding the Law of Conservation of Mass1 objectives
  • Retrieve and apply knowledge of and use the law of conservation of mass.
Mass Changes in Non-Enclosed Systems During Chemical Reactions1 objectives
  • Account for any observed changes in mass in non- enclosed systems during a chemical reaction and explain them using the particle model.
Stoichiometry and Limiting Reactants (Higher)1 objectives
  • Develop knowledge and skill in the stoichiometry of an equation from the masses of reactants and products and explain the effect of a limiting quantity of a reactant.
Calculating Masses from Balanced Equations (Higher Tier)1 objectives
  • Apply a balanced equation to calculate masses of reactants or products.
Understanding Endothermic and Exothermic Reactions1 objectives
  • Develop knowledge and skill in between endothermic and exothermic reactions on the basis of the temperature change of the surroundings.
Understanding Reaction Profiles: Exothermic and Endothermic Reactions1 objectives
  • Develop knowledge and skill in and label a reaction profile for an exothermic and an endothermic reaction.
Understanding Activation Energy1 objectives
  • Account for activation energy as the energy needed for a reaction to occur.
Calculating Energy Changes in Chemical Reactions (Higher Tier)1 objectives
  • Work out energy changes in a chemical reaction by considering bond making and bond breaking energies.
Oxidation and Reduction in Terms of Oxygen Transfer1 objectives
  • Account for reduction and oxidation in terms of loss or gain of oxygen, identifying which species are oxidised and which are reduced.
Understanding Oxidation and Reduction in terms of Electron Transfer (Higher Tier)1 objectives
  • Account for reduction and oxidation in terms of gain or loss of electrons, identifying which species are oxidised and which are reduced.
Acids, Alkalis, and Their Characteristic Ions1 objectives
  • Retrieve and apply knowledge of acids form hydrogen ions when they dissolve in water and solutions of alkalis contain hydroxide ions.
Understanding Neutralisation Reactions1 objectives
  • Communicate the key features of neutralisation as acid reacting with alkali or a base to form a salt plus water.
Understanding Aqueous Neutralisation Reactions1 objectives
  • Develop knowledge and skill in aqueous neutralisation reactions can be generalised to hydrogen ions reacting with hydroxide ions to form water.
Reactions of Carbonates and Some Metals with Acids1 objectives
  • Retrieve and apply knowledge of carbonates and some metals react with acids and write balanced equations predicting products from given reactants.
Understanding Dilute/Concentrated vs. Weak/Strong Acids (Higher)1 objectives
  • Apply and explain the terms dilute and concentrated (amount of substance) and weak and strong (degree of ionisation) in relation to acids.
Understanding Acidity, Alkalinity, and pH1 objectives
  • Retrieve and apply knowledge of relative acidity and alkalinity are measured by pH.
Understanding pH, Acidity, Alkalinity, and Neutrality (Higher Tier)1 objectives
  • Communicate the key features of neutrality and relative acidity and alkalinity in terms of the effect of the concentration of hydrogen ions on the numerical value of pH (whole numbers only).
(Higher) The Relationship Between Hydrogen Ion Concentration and pH1 objectives
  • Apply the idea that as hydrogen ion concentration increases by a factor of ten, the pH value of a solution decreases by one.
Measuring pH: Indicators and pH Meters1 objectives
  • Communicate the key features of techniques and apparatus used to measure pH.
Understanding Product Formation in Electrolysis with Inert Electrodes1 objectives
  • Retrieve and apply knowledge of metals (or hydrogen) are formed at the cathode and non-metals are formed at the anode in electrolysis using inert electrodes.
Electrolysis of Molten Binary Ionic Compounds1 objectives
  • Use evidence to predict the products of electrolysis of binary ionic compounds in the molten state.
Electrolysis of Aqueous Solutions: Competing Reactions1 objectives
  • Communicate the key features of competing reactions in the electrolysis of aqueous solutions of ionic compounds in terms of the different species present.
Understanding Electrolysis: Ions and Electrode Reactions1 objectives
  • Communicate the key features of electrolysis in terms of the ions present and reactions at the electrodes.
Understanding Electrolysis: The Role of Electrodes1 objectives
  • Communicate the key features of the technique of electrolysis using inert and non-inert electrodes.

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