100+ Free IB Chemistry HL Practice Questions

Structure 1: Models of the Particulate Nature of Matter (HL)

Atomic structure, mass spectrometry and calculation of relative atomic mass from isotopic abundance, hydrogen emission spectra and Balmer series, energy level formula E_n = -RH/n^2, successive ionisation energies as evidence for electron shells, full electron configuration including transition metal exceptions Cr 3d5 4s1 and Cu 3d10 4s1, the four quantum numbers (n, l, ml, ms), orbital shapes (s spherical, p dumbbell, d cloverleaf), periodic trends in ionic radii, effective nuclear charge

Structure 2: Models of Bonding and Structure (HL)

Formal charge calculation, resonance and delocalisation in carbonate, nitrate and benzene, expanded octets in SF6 and PCl5, VSEPR with 5-6 electron pairs (trigonal bipyramidal and octahedral) including lone-pair effects on bond angles, molecular orbital theory introduction (sigma vs pi, bond order), hybridisation sp, sp2 and sp3, intermolecular forces including ion-dipole, phase diagrams for water and CO2, triple and critical points

Structure 3: Classification of Matter (HL)

Further classification of compounds, colour in transition metal complexes from d-d transitions, structural and stereoisomerism (geometric cis-trans and optical isomerism) in coordination complexes and organic molecules

Reactivity 1: What Drives Chemical Reactions? (HL)

Born-Haber cycles to calculate lattice enthalpy from enthalpy of formation, atomisation, ionisation energy and electron affinity, entropy change DS = sum S(products) - sum S(reactants), Gibbs free energy DG = DH - T*DS and spontaneity at varying T, DG = -RT ln K linking thermodynamics and equilibrium, enthalpy of solution as lattice enthalpy plus hydration enthalpy

Reactivity 2: How Much, How Fast, How Far? (HL)

Rate equation rate = k[A]^a[B]^b, orders 0/1/2, units of k for each order, integrated rate equations and first-order half-life t1/2 = ln 2 / k, Arrhenius equation k = A e^(-Ea/RT) including graphical determination of Ea, reaction mechanisms with rate-determining step, intermediate vs catalyst, pH and pOH for weak acids using Ka, pKa and pKb, Henderson-Hasselbalch buffer pH = pKa + log([A-]/[HA]), titration curves and indicator selection, solubility product Ksp

Reactivity 3: Electron Sharing and Transfer (HL)

Standard electrode potentials and EMF Ecell, predicting spontaneity using DG = -nFEcell, Faraday's law Q = I*t for electrolysis, chlor-alkali industrial cell, transition metal coloured complexes with crystal field splitting in octahedral and tetrahedral geometries, geometric and optical isomerism in complexes, nucleophilic substitution SN1 vs SN2 mechanisms, electrophilic addition with Markovnikov's rule, electrophilic aromatic substitution on benzene (nitration, halogenation, Friedel-Crafts), condensation reactions, full interpretation of mass spectra, IR and 1H NMR