The shared library
Result library
Every result in the canon, grouped by unit. Press ⌘K to search.
126
results
25
units
6
threads
CU-101 · Atomic Structure & Periodicity 6
| T-001 | Quantised electron orbits give energy levels E_n = -13.6/n^2 eV. | |
| T-002 | Every hydrogen spectral line from a single expression in 1/n^2. | |
| T-003 | Four quantum numbers label every electron in an atom. | |
| T-004 | Aufbau order, Hund's rule and the Pauli principle fix ground-state configurations. | |
| T-005 | Effective nuclear charge explains atomic size and ionisation energy across the table. | |
| T-006 | Electrons are ejected only above a threshold photon energy. |
CU-102 · Chemical Bonding 6
| T-007 | Lattice energy extracted from a thermodynamic cycle. | |
| T-008 | Shared and lone pairs from electron bookkeeping. | |
| T-009 | Electron-pair repulsion predicts molecular geometry. | |
| T-010 | sp, sp2 and sp3 mixing rationalises bond angles. | |
| T-011 | Bonding and antibonding combinations give bond order and magnetism. | |
| T-012 | Unequal sharing produces dipole moments. |
CU-103 · Stoichiometry & the Mole 5
| T-013 | Linking the mass of a sample to the number of particles. | |
| T-014 | From composition by mass to a chemical formula. | |
| T-015 | Which reactant caps the theoretical yield. | |
| T-016 | Equal volumes of gas contain equal numbers of molecules. | |
| T-017 | Molarity and the c1V1 = c2V2 relation. |
CU-104 · States of Matter & Gases 5
| T-018 | PV = nRT, assembled from the empirical gas laws. | |
| T-019 | Pressure as the rate of molecular momentum transfer to the walls. | |
| T-020 | Temperature sets the spread of molecular speeds. | |
| T-021 | Real gases corrected for molecular size and attraction. | |
| T-022 | Effusion rate varies inversely with the square root of molar mass. |
CU-105 · Introduction to Organic Chemistry 5
| T-023 | The reactive handles that organise organic chemistry. | |
| T-024 | One formula, many distinct molecules. | |
| T-025 | Molecular handedness and its measurable signature. | |
| T-026 | The energy landscape of rotation about single bonds. | |
| T-027 | Counting rings and multiple bonds from a molecular formula. |
CU-106 · Chemical Energetics 4
| T-028 | Enthalpy is a state function, so reaction paths are interchangeable. | |
| T-029 | Reaction enthalpy from tabulated formation values. | |
| T-030 | Estimating reaction enthalpy from bonds broken and formed. | |
| T-031 | Measuring heat at constant pressure and at constant volume. |
CU-201 · Chemical Thermodynamics 6
| T-032 | Internal energy change as heat plus work. | |
| T-033 | Spontaneity as the increase of total entropy. | |
| T-034 | G = H - TS decides spontaneity at constant T and P. | |
| T-035 | The relation dG-standard = -RT ln K. | |
| T-036 | How vapour pressure varies with temperature. | |
| T-037 | Entropy drives spontaneous mixing of ideal solutions. |
CU-202 · Chemical Kinetics 6
| T-038 | How concentration controls the rate of reaction. | |
| T-039 | Concentration-time behaviour for zero, first and second order. | |
| T-040 | Temperature dependence of rate and the activation energy. | |
| T-041 | Rate from collision frequency, energy and orientation. | |
| T-042 | Rate from the activated complex at the barrier top. | |
| T-043 | Deriving observed rate laws from a mechanism. |
CU-203 · Chemical Equilibrium 5
| T-044 | The equilibrium constant expression from forward and reverse rates. | |
| T-045 | How an equilibrium responds to a disturbance. | |
| T-046 | Predicting the direction of net change. | |
| T-047 | Gas-phase equilibrium constants and the gas law. | |
| T-048 | Equilibria of sparingly soluble ionic solids. |
CU-204 · Acids, Bases & Buffers 5
| T-049 | Acids and bases as proton donors and acceptors. | |
| T-050 | Kw and the definition of the pH scale. | |
| T-051 | Buffer pH from the acid-to-base ratio. | |
| T-052 | Equivalence points and the choice of indicator. | |
| T-053 | Stepwise dissociation and successive constants. |
CU-205 · Electrochemistry 5
| T-054 | Cell potential assembled from half-reactions. | |
| T-055 | How cell potential depends on concentration. | |
| T-056 | Charge passed and moles of product deposited. | |
| T-057 | The relation dG = -nFE. | |
| T-058 | Ranking oxidising and reducing strength. |
CU-206 · Organic Reaction Mechanisms 6
| T-059 | Two contrasting routes for nucleophilic substitution. | |
| T-060 | Forming alkenes by loss of a leaving group. | |
| T-061 | Regiochemistry of addition to alkenes. | |
| T-062 | Directing and activating effects on the benzene ring. | |
| T-063 | The reactivity of the carbon-oxygen double bond. | |
| T-064 | Intermediates, transition states and the rate-determining step. |
CU-207 · Coordination Chemistry 5
| T-065 | d-orbital splitting in an octahedral ligand field. | |
| T-066 | Why coordination complexes are coloured. | |
| T-067 | Entropy stabilises multidentate complexes. | |
| T-068 | Geometric and optical isomers of coordination compounds. | |
| T-069 | Predicting the shapes of metal complexes. |
CU-301 · Quantum Chemistry 6
| T-070 | Quantised energies as a consequence of confinement. | |
| T-071 | Atomic orbitals as exact solutions of the Schrodinger equation. | |
| T-072 | An upper bound on the ground-state energy. | |
| T-073 | pi-electron energies of conjugated molecules. | |
| T-074 | Separating slow nuclei from fast electrons. | |
| T-075 | Building molecular orbitals from atomic ones. |
CU-302 · Spectroscopy 6
| T-076 | Absorbance proportional to concentration and path length. | |
| T-077 | Bond lengths from the rigid-rotor microwave spectrum. | |
| T-078 | The harmonic oscillator and vibrational selection rules. | |
| T-079 | Reporting the nuclear environment through resonance. | |
| T-080 | Electronic transitions and chromophores. | |
| T-081 | Molecular mass and structure from fragmentation. |
CU-303 · Statistical Thermodynamics 5
| T-082 | The bridge from energy levels to thermodynamics. | |
| T-083 | How molecules populate available energy levels. | |
| T-084 | An average of (1/2)kT per quadratic degree of freedom. | |
| T-085 | Boltzmann's S = k ln W. | |
| T-086 | The Einstein and Debye models of solids. |
CU-304 · Solid State & Materials Chemistry 5
| T-087 | Describing periodic solids from a repeating motif. | |
| T-088 | Diffraction reveals the spacing of crystal planes. | |
| T-089 | How hard spheres fill space. | |
| T-090 | Conductors, insulators and semiconductors from overlapping orbitals. | |
| T-091 | Lattice energy from electrostatics and repulsion. |
CU-305 · Advanced Organic Synthesis 5
| T-092 | Planning a synthesis by working backwards from the target. | |
| T-093 | A concerted, stereospecific cycloaddition. | |
| T-094 | Masking reactivity to control a synthesis. | |
| T-095 | Controlling which stereoisomer is formed. | |
| T-096 | Forming carbon-carbon bonds catalytically. |
CU-306 · Main Group & Inorganic Chemistry 5
| T-097 | Down-group and across-period patterns of behaviour. | |
| T-098 | Predicting the stability of adducts and complexes. | |
| T-099 | Oxidation-state stability seen at a glance. | |
| T-100 | Applying VSEPR across the elements. | |
| T-101 | From basic to acidic across a period. |
CU-307 · Electrochemistry & Interfaces 4
| T-102 | Activity coefficients in dilute electrolyte solutions. | |
| T-103 | Structure of the electrode-solution interface. | |
| T-104 | Electrode current as a function of overpotential. | |
| T-105 | Kohlrausch's law of independent ionic migration. |
CU-308 · Analytical Chemistry 4
| T-106 | Quantifying an analyte by the mass of a precipitate. | |
| T-107 | Separation by differential partition between phases. | |
| T-108 | Combining measurement errors through a calculation. | |
| T-109 | Quantifying a signal against known standards. |
CU-401 · Computational & Theoretical Chemistry 4
| T-110 | A self-consistent mean-field for many electrons. | |
| T-111 | Energy as a functional of the electron density. | |
| T-112 | Representing orbitals for practical computation. | |
| T-113 | Geometries, transition states and reaction paths. |
CU-402 · Chemical Biology & Biochemistry 5
| T-114 | Enzyme rate as a function of substrate concentration. | |
| T-115 | Competitive and non-competitive kinetic signatures. | |
| T-116 | The free-energy balance of the native state. | |
| T-117 | Hydrogen bonding and the double helix. | |
| T-118 | Driving unfavourable reactions with a favourable one. |
CU-403 · Catalysis & Reaction Dynamics 4
| T-119 | Lowering the barrier without being consumed. | |
| T-120 | Surface coverage as a function of pressure. | |
| T-121 | How enzymes achieve enormous rate enhancements. | |
| T-122 | Adsorption, surface reaction and desorption. |
CU-404 · Polymer & Soft Matter Chemistry 4
| T-123 | Chain length and the molar-mass distribution. | |
| T-124 | Two mechanisms for building macromolecules. | |
| T-125 | The freezing of an amorphous polymer. | |
| T-126 | The thermodynamics of polymer solutions. |