by Dr. Chen
Mar 1, 2020

Limited by the time, only topics with a certain level of difficulty and high repeatability will be summarized here.
Underlined topics will be discussed at the online prep session first, others will be discussed if there is time left.
Topics marked by asterisks are mainly for USNCO national exam, which will not be discussed at the online session. Please be aware that more national level topics showed up in the recent locals.
More prep materials for USNCO 2020 can be found at Dr. Chen’s Website, Discord Server and Youtube Channel.

Category 2 - Descriptive Chemistry & Laboratory

Solubility rule

Chlorides vs fluorides

Sulfides & HSAB

Others like sulfates

Volumetric glassware

TC vs TD

Precision of glassware

Error analysis in titrations

Titrant vs analyte (titrate)

Standardization

Rinsing

Category 3 - Gases, Liquids, Solids & Phase Changes

Types and properties of solids

Hardness, bp/mp, conductivity

Existence of molecules

Examples of network covalent solids

Formula and density of crystals

Phase diagrams

Critical point

Density of liquid and solid

Sublimation

Category 5 - Kinetics

Experimental kinetics

Initial rate method

Pseudo-first order reaction

Rate law derivation

Rate-determining step

Steady-state approximation

Pre-equilibrium approximation

Rate dependence on temperature vs E

Arrhenius equation (two forms)

Forward rate vs backward rate dependence on temperature

Category 6 - Equilibrium

Titration curves

Equivalence point vs end point

pH window and indicator

Half equivalence point and buffer region

Strong-strong vs strong-weak

Titration of polyprotic acid

Multiple equilibria

Dissolution by weak electrolyte formation

Dissolution by complex formation

Category 7 - Redox/Electrochemistry

Products of electrolysis

HSO/NaOH

NaCl/KI/CuSO

AgF

E dependence on concentration - Nernst Equation

Concentration cell

K measurement by electrochemistry

E-pH diagram

Category 8 - Atomic Structures/Periodicity

Prediction of decay mode

Cu/C

Radial wavefunction of orbitals

Category 9 - Molecular Structures/Bonding

Molecule orbitals theory

O/O/O/O

NO/NO/NO

Magnetism

Delocalization vs resonance

“rehybridization” and geometry change

Category 10 - Organic Chemistry/Biochemistry

Isomerism

Structural isomers vs stereoisomers

Geometrical Isomers vs optical isomers (chirality)

Enantiomers vs diastereomers

DBE & strategy of isomer counting

Fundamental organic reactions

Acid-base properties of carboxylic acids/phenols/amines

Esterification and saponification

Oxidation of alcohols

Nucleophilic substitutions

Addition of alkenes

Elimination of alcohols/alkyl halides

Aromaticity and aromatic substitutions

……