User:Physchim62/PCSI Chemistry

The architecture of matter

Periodicity

• Introduction to the quantum numbers: n, l, m_l, m_s. Existence of quantised energy levels in the atom, degeneracy of these levels.
• Electronic configuration of an atom or an ion (in the ground state): Pauli’s exclusion principle, Aufbau rules.
• Construction of the periodic table: structure in blocks.
• Trends in certain atomic properties: ionisation energy, electron affinity and Mulliken electronegativity.
• Core electrons, valence electrons.

The quantum model of the atom

• Probability density for the electron in a hydrogen-like atom.
• Polyelectronic atoms: orbital approximation, Slater's effective nuclear charge; energies of hydrogen-like and polyelectronic atoms.
• Atomic radius.
• Ionic radius.

Electronic structure of molecules

• Localised covalent bond: Lewis notation.
• Octet rule.
• Delocalised covalent bond: mesomerism and resonance.
• Prediction of the geometry by the VSEPR method.
• Description of homonuclear diatomic molecules: construction of molecular orbitals by LCAO, orbital overlap; discussion of the MO diagrams of the homonuclear diatomic of the second period.

Low energy interactions

• Van der Waals forces.
• Hydrogen bonds.

Chemical kinetics

Rates in chemical kinetics

• Rates of disappearance of a reactant and of formation of a product, in the case of a closed reactor of uniform composition.
• Progress of a reaction represented by a single stoichiometric equation.

Kinetic factors. Rate laws

• Rate law: reaction with integral order; reactions with non-integral order. Examples.
• Degeneracy of the order.
• Half-life with respect to a limiting reactant, in the case of zeroth, first and second order reactions.
• Arrhenius' law (empirical); activation energy.

Reaction mechanisms in homogeneous kinetics

• Formal kinetics: strictly reversible reactions, parallel reactions, consecutive reactions.
• Steady-state approximation.
• Elementary processes, molecular of a process, reaction intermediates, transition state.
• Qualitative microscopic interpretation of the role of temperature and concentration on the reaction rate.
• Mechanisms by stages. Rate determining step.
• Mechanisms in chain. Chain length.

Structure, reactivity and synthesis in organic chemistry

Stereochemistry of organic molecules

• Newman representations, Cram representations, perspective.
• Configurational stereoisomerism: Z & E, R & S, enantiomers and diastereomers.
• Conformation: ethane, butane, cyclopean, and mono- and disubstituted cyclohexanes.

Reactivity of the carbon-carbon double bond

• Electrophilic addition and radical addition (hydration, hydrohalogenation, halogenation); mechanisms.
• Cleavage by ozonolysis (without mechanism).

Grignard reagents

• Preparation of Grignard reagents, experimental conditions.
• Nucleophilicity and basicity of Grignard reagents.
• Reactions with carbonyl groups (ketones, aldehydes, esters, acyl chlorides, acid anhydrides), with carbon dioxide, with nitriles and with epoxides.

Carbon-halogen bonds

• Nucleophilic substitution reactions: S_N1 and S_N2 limiting mechanisms; stereochemistry.
• Elimination reactions: E2 limiting mechanism, stereochemistry.

Carbon-nitrogen single bonds

• Basicity of amines.
• Nucleophilic reactivity: alkylation (mechanism).

Carbon-oxygen single bonds

• Acid-base properties of alcohols
• Preparation of ethers: Williamson reaction (mechanism)
• Transformation of an alcohol to an monohalogenated derivative: with HX (mechanism); with PX₃ and SOCl₂ (without mechanism).
• Intramolecular dehydration of an alcohol under acidic conditions: formation of an alkene.

Chemical thermodynamics

Applications of the first law of thermodynamics

Models used for the study of transformations

• Isobaric and isochoric reactors, isothermal and adiabatic reactors.
• Heat transfer during isochoric and isobaric transformations.

Standard molar quantities

• Standard states of a pure component: ideal gas and condensed phase; standard molar quantity.
• Transformation in a closed system: standard internal energy, standard enthalpy, variation with temperature.
• Sign of the enthalpy change for and endothermic/exothermic reaction.
• Thermal effects in an isobaric reactor:

Measurement of standard thermodynamic quantities

• Standard enthalpy change of formation of a pure substance.
• Discontinuity in Δ_rH when one of the species changes state.

Equilibria in aqueous solution

• Concept of an acid/base pair, predominance as a function of pH.
• Simple pH calculations (common solutions, buffer solutions).
• Complexes: definition, stability constant (or dissociation constant). Predominance.
• Sparingly soluble compounds, precipitation criteria, solubility.
• Redox pairs: electrode potential; Nernst equation.
• Redox reactions, equilibrium constant, prediction of the direction of a reaction.
• Titrations: acid-base, redox, compleximetric, precipitation.