Singapore JC Subject List - Chemistry (H2)

Core Idea 1: Matter

• 1. Atomic Structure:
• Protons, neutrons, and electrons: their relative charges and masses, and behavior in an electric field.
• Distribution of mass and charge within an atom.
• Determining the number of protons, neutrons, and electrons in atoms and ions.
• Atomic nuclei: proton number and nucleon number, and distinguishing isotopes.
• Electronic energy levels, ionization energies, atomic orbitals, and extranuclear structure.
• Number and relative energies of s, p, and d orbitals.
• Shapes of s, p, and d orbitals.
• Electronic configuration of atoms and ions.
• Factors influencing ionization energies of elements.
• Deducing electronic configurations from successive ionization energy data.
• Interpreting successive ionization energy data in relation to the Periodic Table.

Core Idea 2: Structure and Properties

• 2. Chemical Bonding:
• Ionic, metallic, covalent, and coordinate (dative covalent) bonding.
• Shapes of simple molecules and bond angles.
• Bond polarities and polarity of molecules.
• Intermolecular forces, including hydrogen bonding.
• Bond energies and bond lengths.
• Lattice structure of solids (ionic, simple molecular, giant molecular, hydrogen-bonded, and metallic).
• The effect of structure and bonding on physical properties.
• Deducing structure and bonding from given information.
• 3. The Gaseous State:
• Ideal gas behavior and deviations from it.
• The general gas equation (pV = nRT) and its use in determining Mr.
• Dalton's Law and its use in determining partial pressures of gases in a mixture.
• 4. Theories of Acids and Bases:
• Arrhenius, Brønsted-Lowry, and Lewis theories of acids and bases.
• 5. The Periodic Table:
• Periodicity of atomic and physical properties of elements: variation across Period 3 (sodium to chlorine) and down Group 2 and Group 17. Properties include electronic configuration, atomic radius, ionic radius, ionization energy, electronegativity, melting point, and electrical conductivity.
• Periodicity of chemical properties of elements in Period 3: variation in oxidation number and bonding of oxides (sodium to sulfur) and chlorides (sodium to phosphorus), reactions of these oxides and chlorides with water, and acid/base behavior of oxides and corresponding hydroxides.
• Periodicity of chemical properties down Group 2 and Group 17: reducing agent strength (Group 2), oxidizing agent strength (Group 17), and thermal stability of Group 2 carbonates and Group 17 hydrides.
• Predicting properties of an element based on chemical periodicity.
• Deducing the nature, position in the Periodic Table, and identity of unknown elements.

Core Idea 3: Transformation

• 6. The Mole Concept and Stoichiometry:
• Relative masses of atoms and molecules.
• The mole and the Avogadro constant.
• Calculating empirical and molecular formulae.
• Reacting masses and volumes (of solutions and gases).
• Writing and balancing chemical equations.
• Stoichiometric calculations.
• 7. Chemical Energetics:
• Enthalpy changes (ΔH): formation, combustion, hydration, solution, neutralization, atomization, bond energy, lattice energy, electron affinity.
• Hess's Law and Born-Haber cycles.
• Entropy and Gibbs Free Energy.
• Energy profile diagrams.
• Calculating enthalpy changes from experimental results.
• Effect of ionic charge and radius on lattice energy.
• Constructing energy cycles and performing related calculations.
• Predicting entropy changes and spontaneity of reactions.
• 8. Reaction Kinetics:
• Rate equations, orders of reaction, rate constants.
• Activation energy.
• Effect of concentration, temperature, and catalysts on reaction rate.
• Homogeneous and heterogeneous catalysis.
• Enzymes as biological catalysts.
• 9. Chemical Equilibria:
• Reversible reactions and dynamic equilibrium.
• Le Chatelier's Principle.
• Equilibrium constants (Kc and Kp).
• Calculating equilibrium constants and quantities at equilibrium.
• The Haber process.

Extension Topics

• 10. Chemistry of Aqueous Solutions:
• 10.1 Acid-base Equilibria: Acid dissociation constants (Ka and pKa), base dissociation constants (Kb and pKb), the ionic product of water (Kw), pH, pH indicators, buffer solutions.
• 10.2 Solubility Equilibria: Solubility product (Ksp), common ion effect, complex ion formation.
• 11. Organic Chemistry:
• 11.1 Introduction: Empirical, molecular, and structural formulae; functional groups and naming organic compounds; common terms for organic reactions and reactivities; shapes of organic molecules; sigma (σ) and pi (π) bonds.
• 11.2 Isomerism: Constitutional (structural) isomerism, cis-trans isomerism, enantiomerism.
• 11.3 Hydrocarbons: Alkanes, alkenes, arenes, and hydrocarbons as fuels.
• 11.4 Halogen Derivatives: Halogenoalkanes, halogenoarenes, and relative strength of the C-Hal bond.
• 11.5 Hydroxy Compounds: Alcohols, phenol, and the tri-iodomethane test.
• 11.6 Carbonyl Compounds: Aldehydes, ketones, and characteristic tests.
• 11.7 Carboxylic Acids and Derivatives: Carboxylic acids, acyl chlorides, esters.
• 11.8 Nitrogen Compounds: Amines, amides, amino acids, proteins.
• 12. Electrochemistry:
• Redox processes: electron transfer and changes in oxidation number.
• Electrode potentials: standard electrode potentials (E°), the redox series, standard cell potentials (E°cell), batteries, and fuel cells.
• Electrolysis: factors affecting the amount of substance liberated, the Faraday constant, the Avogadro constant, and industrial uses of electrolysis.
• 13. An Introduction to the Chemistry of Transition Elements:
• General physical and chemical properties of the first set of transition elements (titanium to copper).
• Color of complexes.
• Practical Assessment: Details regarding practical skills assessment can be found in the syllabus document.