General Chemistry
Atoms, elements, bonding, reactions, and the periodic organization of matter
Elements of Chemical Matter and Change
Chemistry studies matter at the scale where atoms and molecules determine macroscopic properties. The irreducible elements:
- Atoms and Elements — the periodic table organizes them by electron configuration and recurring properties (valence, electronegativity, reactivity).
- Electrons and Bonds — ionic, covalent, metallic bonding as ways electrons lower energy by achieving stable configurations.
- Molecules and Compounds — discrete or extended structures with specific geometries and properties.
- Reactions — rearrangements of atoms that conserve mass while transforming energy and properties.
- Energy and Equilibrium — enthalpy, entropy, and the drive toward minimum free energy.
These compose the material world. Bonds compose molecules; reactions transform one set of molecules into another; the periodic table is the master form that predicts behavior across the entire domain.
Conservation, Periodicity, and Stoichiometric Inference
The deductive core rests on conservation laws (mass, charge, energy) and the periodic law. From electron configuration one infers valence and bonding preferences. From a balanced equation one infers exact mole ratios and limiting reagents. Le Chatelier’s principle is a powerful qualitative inference rule for how equilibria respond to stress. These rules are quantitative when combined with measured equilibrium constants and thermochemical data.
Measurement and Observation in Chemistry
Chemistry is intensely experimental: titration, spectroscopy (IR, NMR, UV-Vis, mass spec), calorimetry, chromatography, and diffraction for structure. Rates are measured directly; equilibrium constants from concentrations at equilibrium; bond energies from thermochemistry or spectroscopy. Causal links between structure (bond lengths, angles, electronics) and reactivity are established through systematic variation of substituents and conditions.
Procedures of Chemical Reasoning and Synthesis
The two procedures above (stoichiometry and reaction prediction/mechanism) are the daily algorithmic work of chemists. They are taught rigorously, supported by databases and computational tools (DFT for energies, retrosynthetic planners), and directly enable the engineering lens. Every successful synthesis is the execution of a carefully designed algorithm.
Chemical Systems as Reactive Dynamical Systems
A reaction vessel is a system with stocks of reactants and products, flows of forward and reverse reactions (plus heat), and balancing feedback that drives the system to equilibrium. Catalysts change the kinetics without shifting the equilibrium position. Autocatalytic and oscillatory reactions demonstrate richer dynamics. The same stock-flow ontology used for biological populations and economic systems applies directly to chemical reactors.
Chemical Process Design and Green Chemistry
Chemical engineering is the optimization of reaction systems at scale under real constraints. Objectives include high yield/selectivity, low energy and waste (atom economy), safety, and sustainability. Constraints are thermodynamic (you cannot violate ΔG), kinetic (rates and activation energies), safety (exotherms, toxicity), and economic/environmental (solvent choice, catalyst recovery, life-cycle impact).
Modern practice emphasizes catalysis, flow chemistry, biocatalysis, and computational design to meet these constraints while producing the molecules society needs.