International Baccalaureate IB Chemistry

Identify the positions of metals, metalloids and non‑metals in the periodic table. The four blocks associated with the sublevels s, p, d, f should be recognised.

Deduce the electron configuration of an atom up to $Z = 36$ from the element’s position in the periodic table and vice versa.

Groups are numbered from 1 to 18. 

The classifications “alkali metals”, “halogens”, “transition elements” and “noble gases” should be known.

Explain the periodicity of atomic radius, ionic radius, ionisation energy, electron affinity and electronegativity.

Trends down a group (metallic/non‑metallic character)

Describe and explain the reactions of group 1 metals with water, and of group 17 elements with halide ions.

Deduce equations for the reactions with water of the oxides of group 1 and group 2 metals, carbon and sulfur.

Deduce the oxidation states of an atom in an ion or a compound.

Discontinuities occur in the trend of increasing first ionisation energy across a period.

Explain how these discontinuities provide evidence for the existence of energy sublevels. 

Explanations should be based on the energy of the electron removed, rather than on the “special stability” of filled and half‑filled sublevels.

Transition elements have incomplete d‑sublevels that give them characteristic properties.

Recognise properties, including: variable oxidation state, high melting points, magnetic properties, catalytic properties, formation of coloured compounds and formation of complex ions with ligands.

Variable oxidation states of transition elements

The formation of variable oxidation states in transition elements can be explained by the fact that their successive ionisation energies are close in value. 

Deduce the electron configurations of ions of the first‑row transition elements.

Transition element complexes are coloured due to the absorption of light when an electron is promoted between the orbitals in the split d‑sublevels.

The colour absorbed is complementary to the colour observed. 

Apply the colour wheel to deduce the wavelengths and frequencies of light absorbed and/or observed.

Organic compounds can be represented by different types of formulas.

These include empirical, molecular, structural (full and condensed), stereochemical and skeletal. Identify different formulas and interconvert molecular, skeletal and structural formulas. 

Construct 3D models (real or virtual) of organic molecules.

Functional groups give characteristic physical and chemical properties to a compound. Organic compounds are divided into classes according to the functional groups present in their molecules.

Identify the following functional groups by name and structure: halogeno, hydroxyl, carbonyl, carboxyl, alkoxy, amino, amido, ester, phenyl.

A homologous series is a family of compounds in which successive members differ by a common structural unit, typically CH₂. Each homologous series can be described by a general formula.

Identify the following homologous series: alkanes, alkenes, alkynes, halogenoalkanes, alcohols, aldehydes, ketones, carboxylic acids, ethers, amines, amides and esters.

Successive members of a homologous series show a trend in physical properties.

Describe and explain the trend in melting and boiling points of members of a homologous series.

“IUPAC nomenclature” refers to a set of rules used by the International Union of Pure and Applied Chemistry to apply systematic names to organic and inorganic compounds.

Apply IUPAC nomenclature to saturated or mono-unsaturated compounds that have up to six carbon atoms in the parent chain and contain one type of the following functional groups: halogeno, hydroxyl, carbonyl, carboxyl.

Structural isomers are molecules that have the same molecular formula but different connectivities.

Recognise isomers, including branched, straight‑chain, position and functional‑group isomers.

Stereoisomers have the same constitution (atom identities, connectivities and bond multiplicities) but different spatial arrangements of atoms.

Describe and explain the features that give rise to cis‑trans isomerism; recognise it in non‑cyclic alkenes and $C_3$ and $C_4$ cycloalkanes. 

Draw stereochemical formulas showing the tetrahedral arrangement around a chiral carbon. 

Describe and explain a chiral carbon atom giving rise to stereoisomers with different optical properties. 

Recognise a pair of enantiomers as non‑superimposable mirror images from 3D modelling (real or virtual).

Infrared (IR) spectra can be used to identify the type of bond present in a molecule.

Interpret the functional‑group region of an IR spectrum, using a table of characteristic frequencies (wavenumber $\mathrm{cm}^{-1}$). 

Include reference to the absorption of IR radiation by greenhouse gases.