Learning Objectives in all 10 Topics
Introduction
Descriptive Chem and Laboratory [Q7-12]
Stoichiometry [Q1-6]
- There is NO official syllabus for the USNCO other than 10 Topics, all these learning objectives are summarized by Dr. Chen based on the most recent years of local and national exams;
- The latest learning objective is updated here;
- USNCO exams are based on college-level general Chemistry, such as Advanced Placement (AP) Chemistry. Those topics beyond the scope of AP Chem are labeled with * except the orgo part;
- In the orgo part, * represent the more advanced topics, mainly for national exam;
- the self-assessment is a new module added to the website, enjoy! credit goes to the author of code: Andrew Ni.
Stoichiometry [Q1-6]
Descriptive Chem and Laboratory [Q7-12]
Stoichiometry [Q1-6]
- concepts and conversion of mol, Avogadro's constant, molar mass, etc
- mass percent, empirical formula
- limiting reactant, percent yield
- solution stoichiometry
- combustion analysis
- mixture analysis
- *colligative properties
- [lab] determination of the formula of copper sulfate hydrate
- [lab] quantitative analysis of sodium carbonate and sodium bicarbonate in solid
- *[lab] measurement of the melting point depression of solution*
- *[lab] determination of mass percent of H2O2(aq) - MnO2 as catalyst
Descriptive Chem and Laboratory [Q7-12]
Descriptive Chem and Laboratory [Q7-12]
Descriptive Chem and Laboratory [Q7-12]
- flame test, color of ions, heat of dissolution, etc.
- solubility rules
- reaction types
- *properties of representative metals/nonmentals
- strong/weak electrolytes, acid-base property of salt solutions
- volumetric glassware
- titrations and error analysis
- spectrometry and Beer's law
- *typical gas evolution and redox reactions
- [demo] conductivity of Ba(OH)2 with H2SO4 added
- [lab] reaction types and net-ionic equations
- [lab] qualitative analysis of ions
- [lab] analysis of food dyes in beverages
- [lab] measurement of the mass percent of copper in brass
- *[lab] gravimetric analysis of calcium in hard water
- New: a lab module is added
IMFs and States of Matter [Q13-18]
IMFs and States of Matter [Q13-18]
Descriptive Chem and Laboratory [Q7-12]
- analysis of IMFs, such as LDFs, dipole-dipole, ion-dipole, hydrogen bonds
- relationship between IMFs and physical properties, such as mp, bp, vapor pressure, etc.
- *phase diagram
- ideal gas law and partial pressure
- kinetic molecular theory, effusion and Graham's law
- dynamic equilibrium of vapor pressure
- lattice energy and solid types
- *unit cell models and solid density
- [lab] separation of food dyes using paper chromatography
- [lab] measurement of the molar mass of an unknown volatile liquid
- [demo] air bag design - baking soda and vinegar
Thermodynamics [Q19-24]
IMFs and States of Matter [Q13-18]
Thermodynamics [Q19-24]
- calorimetry
- concepts of q, w, H, S, etc.
- *U vs H, qp vs qv
- deltaH of formation and Hess's law
- estimation of deltaH using bond energies
- 1st and *2nd law of thermodynamics
- sign prediction of deltaS
- deltaG and spontaneity
- *deltaG of formation
- dependence of deltaG with T
- *van't Hoff equation (lnK vs T)
- *deltaG vs deltaG (standard)
- [lab] measurement of the molar neutralization or dissolution heat
Kinetics [Q25-30]
IMFs and States of Matter [Q13-18]
Thermodynamics [Q19-24]
- relative rates
- integrated rate laws of 0th, 1st, 2nd order reaction
- rate constant and half-life
- *kinetics of nuclear decay
- rate law from initial rates
- collision model/transition-state model, activation energy
- Arrhenius equation (k vs T)
- *derivation of rate law using approximations, SSA, PEA, etc.
- *kinetics analysis of reversible, parallel, and consecutive reactions
- reaction coordinate diagram and catalyst
- [lab] pseudo kinetic analysis of the fading of crystal violet
- *[lab] measurement of rate law of the disproportionation of thiosulfate in acid
- *[lab] measurement of the activation energy
Equilibrium [Q31-36]
Atomic Structures/Periodicity [Q43-47]
Redox and Electrochemistry [Q37-42]
- concepts of equilibrium, K, Q, etc
- calculation with K - RICE table
- *Kc vs Kp
- Le Chatelier principle
- Ka, Kb, pH calculation of strong and weak acids/bases
- titration, titration curve and indicator
- buffer and Henderson-Hasselbalch equation
- *multiple equilibria involving dissolution and complex, etc.
- solubility and Ksp
- *solubility vs pH
- *advanced equilibrium with mass-balance and charge-balance equations
- [lab] determination of K for the formation of FeSCN2+
- [demo] application of LCP - NO2/N2O4, cobalt, chromate/dichromate equilibrium
- [lab] acid-base titration and its titration curve
- [lab] preparation and properties of buffers
- *[lab] titration of NaHCO3/Na2CO3 mixture using two indicators
Redox and Electrochemistry [Q37-42]
Atomic Structures/Periodicity [Q43-47]
Redox and Electrochemistry [Q37-42]
- concepts of redox and oxidation states
- balance of redox equations/half equations
- Galvanic cell model, cathode, anode, salt bridge, line notation
- standard reduction potential and SHE
- *potential calculation from related half reactions
- LCP in redox equilibrium
- *Nernst equation
- *measurement of Ksp using electrochemical method
- *Faraday's law of electrolysis
- *electrolysis of aqueous solutions
- *E-pH relation and diagram
- [lab] redox titration of H2O2 or oxalate with permanganate
Atomic Structures/Periodicity [Q43-47]
Atomic Structures/Periodicity [Q43-47]
Atomic Structures/Periodicity [Q43-47]
- evolution of atomic models
- Borh's model and *hydrogen emission spectrum
- orbital and *quantum numbers
- *wavefunctions and nodes
- *nuclear decay models, alpha, beta, positron, etc.
- electron configuration and *magnetism
- periodic table and periodic trends such as atomic/ionic size, ON, IE, EA, EN, etc.
- photoelectric effect
Molecular Structures/Bonding [Q48-Q54]
Organic Chemistry/Biochemistry [Q55-60]
Atomic Structures/Periodicity [Q43-47]
- Lewis structures, formal charges
- resonances
- bond polarity and dipole moment
- VSEPR and molecular geometry
- molecular polarity
- *isomers of complex (CN = 4 or 6)
- hybridization model
- *conjugation and rehybridization
- *molecular orbital model
Organic Chemistry/Biochemistry [Q55-60]
Organic Chemistry/Biochemistry [Q55-60]
Organic Chemistry/Biochemistry [Q55-60]
- conjugation and delocalization
- *stability of carbocation and free radical
- common functional groups
- acid-base properties of organic compounds such as acid and amines
- types of isomers
- cis vs trans
- isomer counting
- chirality and concepts of enantiomers/diastereomers
- *conformation of cyclohexane
- esterification and saponification
- nucleophilic substitutions
- elimination of alkyl halides and alcohols
- oxidation of alcohols
- addition of alkenes
- aromaticity and aromatic substitutions
- structures of polysaccharides, proteins, nucleic acids, etc.
- polymerization
- *more advanced orgo, such as acidity of terminal alkynes, aldol, acetal/semiacetal, reducing sugar, organometallic reagents, etc.
- [demo] melting point measurement of organic compounds
- [demo] acid-base extraction
- [lab] recrystallization of benzoic acid
Trends of USNCO 2016-20
Organic Chemistry/Biochemistry [Q55-60]
Organic Chemistry/Biochemistry [Q55-60]
- to be added
Survey: the Impact of the Two-Student Cap on School Teams
This unofficial and anonymous survey aims to gather feedback from US National Chemistry Olympiad (USNCO) participants on the effects of the "top 2 per school" rule and explore potential improvements to ensure both fairness and strong team-based chemistry education.
Your participation (< 2 mins) and sharing of this survey with other participants and chemistry teachers are greatly appreciated.