Unit 1: Chemical Fundamentals — Structure, Properties and Reactions
Unit Objectives
Describe ideas and findings about properties and structure of atoms and materials, and chemical reactions in terms of reactants, products, and energy change.
Apply understanding of properties and structure of atoms and materials, and chemical reactions in terms of reactants, products, and energy change.
Analyse data about properties and structure of atoms and materials, and chemical reactions in terms of reactants, products, and energy change.
Interpret evidence about properties and structure of atoms and materials, and chemical reactions in terms of reactants, products, and energy change.
Evaluate processes, claims, and conclusions about properties and structure of atoms and materials, and chemical reactions in terms of reactants, products, and energy change.
Investigate phenomena associated with properties and structure of atoms and materials, and chemical reactions in terms of reactants, products, and energy change.
Topic 1: Properties and Structure of Atoms
Atomic Structure
Describe that atoms can be modelled as a nucleus surrounded by electrons in distinct energy levels.
Discriminate between the terms atomic number (Z), mass number (A), and isotopes of an element.
Apply the nuclear symbol notation to determine the number of protons, neutrons, and electrons in atoms, ions, and isotopes.
State the relative energies of the s, p, and d orbitals.
Apply the Aufbau principle, Hund’s rule, and the Pauli exclusion principle to write electron configurations for atoms and ions up to Z = 36.
Determine full and condensed electron configurations for atoms and ions up to Z = 36.
Identify the electron configuration of Cr and Cu as exceptions.
Explain how successive ionisation energy data is related to the electron configuration of an atom.
Isotopes
Describe that isotopes are atoms of the same element that have different numbers of neutrons.
State that isotopes can be represented in the form AX (IUPAC) or X-A.
Identify that isotopes of an element have the same electron configuration and similar chemical properties but different physical properties.
Explain that the relative atomic mass of an element is the ratio of the weighted average mass per atom of the naturally occurring form of the element to 1/12 the mass of an atom of carbon-12.
Analytical Techniques
State that mass spectrometry involves the ionisation of substances and the separation and detection of the resulting ions.
Analyse mass spectrometry spectra to determine the isotopic composition of elements, the relative atomic mass of an element, and percentage abundances of the isotopes.
Discriminate between absorption and emission line spectra.
Explain that flame tests and atomic absorption spectroscopy (AAS) rely on electron transfer between atomic energy levels.
Explain that the emission spectrum of hydrogen provides evidence for the existence of electrons in discrete energy levels (Bohr model).
Analyse flame tests and AAS to identify elements and determine the concentration of metallic ions in solution.
Topic 2: Properties and Structure of Materials
Compounds and Mixtures
State that pure substances may be elements or compounds.
Identify that pure substances have distinct measurable properties, while mixtures have properties dependent on their components.
Discriminate between heterogeneous and homogeneous mixtures.
Analyse data to determine the physical properties of pure substances and mixtures.
Bonding and Properties
Describe the properties of ionic, covalent, and metallic compounds.
Explain that the type of bonding within substances determines their physical properties.
Explain the properties of ionic compounds by modelling ionic bonding as ions arranged in a crystalline lattice structure.
Discriminate between ionic and metallic bonding.
Explain the properties of covalent compounds by modelling covalent bonding.
Discriminate between covalent molecules, giant covalent networks, and allotropes of carbon.
Explain that hydrocarbons, including alkanes, alkenes, and benzene, have different chemical properties.
Analyse data to determine the properties, structure, and bonding of ionic, covalent, and metallic compounds.
Science Inquiry
Investigate flame tests to identify elements.
Analyse mass spectra and isotopes.
Use atomic absorption spectroscopy (AAS) to determine the concentration of aqueous metallic ions.
Investigate the separation of mixtures based on physical properties.
Examine the properties of ionic, metallic, and covalent compounds.
Conduct tests to distinguish alkanes and alkenes.
Mole concept and law of conservation of mass
State that a mole is a precisely defined quantity of matter equal to Avogadro’s number of particles.
State the law of conservation of mass.
Explain that the mole concept relates mass, moles and molar mass.
Apply the mole concept to calculate the mass of reactants and products; amount of substance in moles; number of representative particles; and molar mass of atoms, ions, molecules and formula units. (Formula: moles (𝑛) = mass (m) / molar mass (M))
Determine the percentage composition from relative atomic masses; empirical formula of a compound from the percentage composition by mass; and molecular formula of a compound from its empirical formula and molar mass.
Determine limiting reactants.
Discriminate between experimental and theoretical yield.
Analyse data to determine percentage and theoretical yield. (Formula: percentage yield (%) = (experimental yield / theoretical yield) × 100)
Topic 3: Chemical reactions — reactants, products and energy change
Chemical reactions
Identify that chemical reactions and phase changes involve energy changes, commonly observable as changes in the temperature of the surroundings and/or the emission of light.
Determine balanced chemical equations, including state symbols (s), (l), (g) and (aq), for a variety of reactions, e.g. single displacement, double-displacement, acid-base, combustion, combination, decomposition and simple redox reactions.
Exothermic and endothermic reactions
State that heat is a form of energy, and that temperature is a measure of the average kinetic energy of the particles.
Explain how endothermic and exothermic reactions relate to the law of conservation of energy and the breaking and reforming of bonds.
Discriminate between exothermic and endothermic reactions.
Sketch enthalpy level diagrams for exothermic and endothermic reactions.
Analyse enthalpy level diagrams and thermochemical equations to determine the relative stabilities of reactants and products, and the sign of the enthalpy change (ΔH) for a reaction.
Explain, in terms of average bond enthalpies, why reactions are exothermic or endothermic.
Identify the limitations of using average bond enthalpies to calculate enthalpy change.
Calculate the heat change (Q) for a substance given the mass, specific heat capacity and temperature change. (Formula: Q = mcΔT)
Calculate the enthalpy change (ΔH) for a reaction given temperature changes, quantities of reactants and mass of water. (Formula: ΔH = H(products) – H(reactants))
Analyse data for heat of combustion, heat of neutralisation and reactions in aqueous solutions to determine heat, mass, specific heat capacity, temperature and enthalpy change.
Science inquiry
Investigate types of chemical reactions.
Investigate limiting reagent/s and percentage yield.
Investigate the empirical formula of a compound from reactions involving mass change.
Investigate the enthalpy change of a reaction, e.g. calorimetry or Hess’s Law.
