CODS Competitor's Guide

By Nicolai Bogo Stabell (Stabell#6680) & Kwanwoo Park (fizzest#0001)

Version 2.0 (August 29th, 2022)

Author Note: The guide is an ambitious attempt to cover everything that a competitor needs to know about our competition structures. This guide is written as detailed as possible for the competitor to reference.

Jeremy's Note: The guide on the website (you're reading it!) is not guaranteed to be as complete or up-to-date as the Google Docs. As such, please check the Google Docs.

Orange's Note: There may be typos when transferring from the Google Docs to the website. As such if you discover a typo, please do let the staff know.

Introduction

The guide is an ambitious overview of our four competition’s structures, tier system and placements. This document will be reviewed and updated to reflect any changes during the year.

Competitions

Our competitions are seasonal, the first in October and latest in July. Each competition has a distinct exam format and emphasis, but share some similarities. Most competitions utilize our tier system - separate question sets from bronze to gold tier. Most also have two rounds for each tier: a Main round for all participants and a Final round for its highest scoring participants. The very best total scorers receive awards, diplomas, and even a promotion to the next tier.

Autumn Chemistry Online Tournament (ACOT)

The first competition of each year will be our autumn competition, which its outcome is heavily dictated by your accuracy, but your speed as well.

In the Main round, participants are expected to take 20 Multiple Choice Questions within 60 minutes. Some questions may have multiple answers. Guessing or incorrect answers will be penalized in the main round. Participants that do exceptionally well within the main round will advance to the final round.

The Final round is composed of four Free Response Questions with multiple sections which participants are expected to complete within 120 minutes. Each tier will have an Organic, Inorganic, Analytical, and Physical Chemistry question.

Each participant’s score is composed of accuracy (80%) and time of completion, also known as speed (20%).

More information about the competition and our mathematical model can be found in the ACOT 2022 Rulebook.

Winter Chemistry Competition (WCC)

WCC emphasizes your ability to use teamwork to solve questions in a multiple round competition. Any combination of up to four members (regardless of tier) may compete together in this competition.

The first round is composed of a 4-question 90 minute individual exam. Participants may expect at least one question from any of the four topics in this exam: physical, inorganic, organic, and analytical chemistry.

In the second round, bronze and silver tier teams will work for 120 minutes on a 6-question closed-book team exam that is time-intensive and truly puts teamwork to the test.

Those competing in the gold tier will work together for 240 minutes in a 4-question, open Internet exam (e.g. Open Round of SOCC ’21) that tests the teams’ knowledge and capability to tackle real-life scenarios and problems that is hard to come by in traditional chemistry olympiad.

The Final round will be Cleaving Bonds, a fast-paced teamwork competition with live-scoring present. Each team will be given twelve rounds of three short-answer questions that become increasingly difficult with only 90 minutes on the clock. As all teams work through their rounds, their scores will be graded live on the spot during the competition, making it very exciting to watch as both a participant and a spectator.

Spring Open Chemistry Competition (SOCC)

SOCC is a competition modeled after the USNCO exam (United States National Exam), as one of the most competitive national chemistry olympiads.

For the Main round, all participants will take the same USNCO National Part I style exam, involving 60 multiple-choice questions. All participants will be given 90 minutes to attempt the exam. Participants that do exceptionally well will advance to the final round.

The Final round is a USNCO National Part II style exam (8 free-response questions, 105 minutes). Those that do exceptionally well in the final round will be awarded with awards and prizes!

Summer Chemistry Olympiad (SChO)

SChO is our summer competition, based on the IChO (International Chemistry Olympiad) structure. Unlike our other competitions, there is only one round for the SChO and all the problems are free responses. The exam format depends on the tier a competitor chooses to participate in:

Tier# of QuestionsTime Allocated
Bronze42 hours(120 minutes)
Silver73.5 hours (210 minutes)
Gold95 hours (300 minutes)

Topics involved in this competition are physical, inorganic, organic, and analytical chemistry.

The Tier System

Our tier system is inspired by the one used in the United States of America Computing Olympiad (USACO). The goal of the tier system is to create more differentiation in our competitions, allowing more people to participate at a level that is appropriate for them. The tier system consists of three levels (tiers) which corresponds to:

  • Bronze Tier: Beginner difficulty which covers A-level/AP Chemistry, and equivalent.
  • Silver Tier: Intermediate difficulty of national/finals level of most countries’ Chemistry Olympiad.
  • Gold Tier: Advanced difficulty between IChO and Mendeleev (Russian Chemistry Olympiad) difficulty.

This system can be found in ACOT, WCC, and SChO. The topics of the three tiers are outlined below:

Bronze Tier

The Bronze Tier is the entry tier at which every person competing in a CODS Competition begins unless placed differently from a Chemistry Olympiad achievement. The average difficulty and problem-solving level for the bronze tier is around A-level/AP Chemistry, and equivalent. We want all competitions to be somewhat challenging for newcomers, although the concepts involved should be relatively straightforward. For the detailed syllabus, check the Appendix (Scroll to the bottom of the page). For book recommendations, tips, and tricks read our Introductory Guide from our website.

Silver Tier

The Silver Tier is a tier higher than the bronze tier. This tier aims for a difficulty around a country's chemistry olympiads national/final level. It involves all topics in the bronze tier and the advanced topics listed below, such as Organic Chemistry (although limited to the knowledge you can find in Klein’s Organic Chemistry or equivalent). For the detailed syllabus, check the Appendix (Scroll to the bottom of the page). For book recommendation, tips and tricks read our Intermediate Guide from our website.

Gold Tier

The Gold Tier is the highest proposed tier for CODS Competitions. The average difficulty and problem-solving level for the gold tier will be of the difficulty of IChO, Mendeleev (IMChO) or higher. It should involve a more sophisticated level of advanced topics and should be very challenging. Therefore, the syllabus for gold tier will always be the current year's IChO exam and preparatory problems, which are released for the upcoming IChO.

Promotion, Demotion, Decay

In each competition, promotion and demotion will occur in order to make sure that all participants are in the tier most useful to them.

TierPromotion RequirementDemotion Requirement*Decay
Bronze15%--
Silver10%5%4
Gold-10%2

*In the case that the total number of participants in a tier who took the competition's exam is 9 or lower, no participants will be demoted.

For example, Silver tier participants who place within the Top 10% of any competition will be promoted to the Gold tier. Additionally, Silver tier participants who do not compete in four consecutive CODS competitions in a row will be subjected to demotion (decayed) to the lower tier.

The decay number indicates the number of competitions that you can not take before you will automatically be demoted. For example, silver tier's decay is four which means that if you are inactive for a whole 4-competition season, you will be demoted to bronze.

If the number of participants in a tier results in a fractional number of participants to be promoted to demoted, the number is rounded to the nearest integer. Also, if one of the rounds contains a free-response exam, participants with score(s) within 2% of the last participant who received promotion, demotion, or round qualification will also receive it.

Based on your country and your achievements in the National Chemistry Olympiad, you will start in a higher tier than bronze.

Placement

If you have an achievement in a competitive chemistry competition from the current or last season, you must be promoted to a higher tier. The tier to which you will be promoted is dependent on the strength of your achievement, which we evaluate in two ways: level of achievement and competitiveness of the contest at which the achievement was made.

We classify the level of achievement into four categories:

  1. Honors: Someone who made Top 100-150 or equivalent.
  2. Camper: Those who made the IChO Selection camp or equivalent.
  3. Those who have been picked for their national team or participated in the International Chemistry Olympiad.
  4. Medalist: Those who have achieved a medal at IChO.

We hope these four categories are comprehensive enough to cover all countries. If not, or if your achievement was in a competition that is not the IChO, don't hesitate to contact the CODS Staff for guidance.

In order to ascertain the competitiveness of the contest, we look at the country's Chemistry Olympiad performance. As a benchmark, we use IChO results for the individual countries - since national competitions work independently to find their nation's four best chemists to represent their country at the IChO.

The model we use divides all participating countries into a competitiveness group system from I to IV based on their percentile performance score. This score is calculated from the numbers of different medals and HM (honorable mentions) received at IChO during the last 10 years. This will be updated after each IChO has been held.

For example, a higher ratio of gold medals compared to other prizes will result in a higher tier. Table 1 below shows the result of these calculations:

Table 1 - Competitiveness tier division of countries based on their last 10 years of results from the IChO. The countries in each group are given in alphabetical order.

GroupPercentileCountries
I100%-60%Australia, Austria, Belarus, Brazil, Bulgaria, China, Chinese Taipei, Czech Republic, Germany, Hungary, India, Indonesia, Iran, Italy, Japan, Kazakhstan, Korea, Lithuania, Poland, Romania, Russia, Serbia, Singapore, Slovakia, Thailand, Turkey, USA, Ukraine, United Kingdom, Vietnam.
II60%-40%Armenia, Azerbaijan, Canada, Denmark, Estonia, Israel, Finland, France, Georgia, Latvia, Malaysia, Mexico, Moldova, Mongolia, Netherlands, New Zealand, Peru, Philippines, Saudi Arabia, Slovenia, Spain, Sri Lanka, Syria, Tajikistan, Turkmenistan, Uzbekistan.
III40%-20%Bangladesh, Belgium, Costa Rica, Croatia, Cyprus, Greece, Ireland, Kyrgyzstan, Luxembourg, Macedonia, Norway, Pakistan, Salvador, Sweden, Switzerland, United Arab Emirates, Uruguay, Venezuela.
IV20%-0%Cuba, Portugal, Iceland, Egypt, Kuwait, Liechtenstein, Montenegro, Nigeria, Oman, Qatar, South Africa, Trinidad and Tobago.

*If a country is not shown in the table it will automatically be in group IV of competitiveness.

In the table below, the three colors represent the three tiers: Bronze, Silver, and Gold. For example, a participant who has achieved Honors level in a competition of group I country will be promoted to silver tier. A participant that achieved IChO level in a country of group III will be silver tier. Regardless of your achievements and countries competitiveness group, you will always be able to fight through the tier system in our competitions.

Table 2 shows what tier you can be promoted to based on the level of achievement for a country's group of competitiveness:

Table 2 - Level of achievement relative to group of competitiveness

  Honors Camper IChO Medallist
I        
II        
III        
IV        

To summarize the process, you must first find out which of the four levels of achievement you belong to. Based on that and your country's group of competitiveness (see table 1) you can with the use of table 2 find which tier you will be promoted to. However, you must always apply to be promoted, which is done in the current competition sign-up from.

It is your job as a participant to inform us about previous achievement and country when sign-up to our competitions. So that we ensure you participate in the correct tier based on your level. If you do not comply with this, you will be punished according to our CODS Honor Code. If you are in doubt or need help, please contact us.

Prizes

Prizes will also be available for our competitors and are rewarded independent of each of the three tiers.

Each diploma will include an associated reward title, which is based on the participant’s individual or team scores.

  • 1st, 2nd, and 3rd place will be recognized as such.
  • High Honors is awarded to the next ~8% of participants.
  • Honors is awarded to the next ~16% of participants.

Some, but not all, of the diploma recipients may also receive a t-shirt or a sticker. The amount of awards given at each competition can be found in the given competition’s Rulebook. In the situation where the number of participants in each tier is lower than 30 participants or 15 teams, adjustments to the number of prizes, titles and diplomas may change. You will be able to find previous competitions and their results on the CODS Wall of Fame (soonTM).

Testing

CODS Identification Number (CIN)

All participants will absolutely need to find out their CIN. You will need this 6-digit number to sign up for a competition and do any other forms. All scores will also be released by CIN.

Find your CIN HERE.

Proctoring Types

This year, we are offering two types of proctoring for all competitions:

  • Physical proctoring (in-person proctoring with a school administrator, teacher, or tutor; choice of print or computer exam format)
  • Online proctoring (online proctoring with video and screen recording, computer exam format)

Exam Times

Physical participants are able to take any given exam (with their proctor) any time during a 7-day window, a full Monday-Sunday week. Online participants are able to take the exam any time during the last 48-hours of this window, Saturday-Sunday. Some competition rounds, such as Cleaving Bonds, may be limited in time slots due to the nature of the competition. Some competitions, such as Cleaving Bonds, may be limited in time slots due to the nature of the competition.

Physical Proctoring

In physical proctoring, participants can have any school administrator, teacher, professor, coach, or tutor proctor (watch you take) the exam. As such, you will have the option to either receive:

  • An email with a google form link containing the exam questions. The very bottom of the form will include a second link to a Submission Form to upload your answers
  • A email with a printable PDF containing the exam questions and a google form link to a Submission Form in which to upload your answers

In order to be physically proctored: you will need to give your proctor’s name, relation (i.e. chemistry teacher), and professional email OR your proctor can sign you up. We will then verify any first time proctors and send all proctors the exam and script in advance.

You do not have to do any online forms of proctoring in in-person proctoring. As such, you will not need to give us access to your screen or camera.

Remote Proctoring

In remote proctoring, participants will receive:

  • An email with a google form link containing the exam questions. The very bottom of the form will include a second link to a Submission Form to upload your answers.

This form will also request two permissions before you can view the exam: video proctoring and screen proctoring.

Video Proctoring

  • Quilgo will ask to access your video camera. Please ensure that your recording device clearly records your face at all times during the exam.
  • Make sure your video device is fully charged or connected to a power cable. Devices must remain powered on during the entire exam.
  • Please test that your webcam functions properly prior to the time of your exam.

Screen Proctoring

  • Quilgo will ask to access your screen. Please ensure that you are sharing your full screen at all time.

As these proctoring forms are necessary to provide a fair testing environment for remote participants, turning off your camera or screen recording any time before you submit your exam may result in your disqualification. Additionally, participants are required to have a functioning webcam (for workspace) and a phone or scanner to scan their hand-written answers for submission. Multi-accounting is considered cheating and will be a network-bannable offense. Testing security is a big focus in CODS competitions and any evidence that confirms cheating will be taken seriously and punished.

In the case you cannot undergo either video or screen proctoring, please request an appeal at chemolyds@gmail.com.

Appendix

The appendix features a detailed syllabus of the bronze and silver tiers. The gold tier uses the IChO standard syllabus and, as such, is not detailed here.

Bronze Tier Syllabus

As shown in the table below, a more detailed description can be found about the bronze tier syllabus.

Analytical Chemistry
Titration
  • Acid and Base (strong, weak, and polyatomic).
  • Choice of indicators.
  • Redox (Permanganate, Iodometric).
Qualitative AnalysisInorganic
  • Cations (NH4+, Na+, K+, Mg2+, Zn2+, Cu2+, Fe2+, Fe3+, Ca2+, Ba2+, Pb2+, Ag+).
  • Anions (NO3-, S2-, SO32-, SO42-, Cl-, Br-, I-, CO32-, PO43-, OH-).
  • Flame colors (Na, Li, K, Ca, Sr, Cu, B).
  • Amphoteric oxides (Zn, Sn, Pb, and Al).
Organic
  • Alkene, halogenoalkane, alcohol, aldehydes, carboxylic acids.
SpectroscopyUV/Visible
  • Dyes: colour vs structure (aromaticity and chromophore).
  • Beer's Law.
General Chemistry
Radioactivity
  • Counting of nucleons.
  • Isotopes.
  • Types of radioactivity.
  • Radioactive decay (alpha, beta, and gamma).
  • Nuclear reactions (alpha and beta decay, positron emission, electron capture, gamma emission, and spontaneous fission).
Chemical Calculations
  • Balancing equations.
  • Stoichiometric calculations.
  • Mass and volume relations (including density).
  • Mass, volume, and mole percent.
  • Empirical formula.
  • Avogadro's number.
  • Concentration calculations.
Inorganic Chemistry
Periodic Trends
  • Main group elements (electron configuration, Pauli exclusion principle, Hund’s rule, electronegativity, electron affinity, first ionization energy, atomic size, ion size, highest oxidation number).
  • Main group trends in physical properties (melting point, boiling point, metal character, magnetic properties, and electrical conductivity)
  • Reactivity series (K, Na, Ca, Mg, Al, C, Zn, Fe, Sn, Pb, H, Cu, Hg, Ag, Au).
Chemical Bonding
  • Bond types (polar/nonpolar and covalent/ionic bonds).
  • Electronegativity (determine type of bond: ionic, polar, and nonpolar).
  • Lewis structures.
  • Octet rule.
  • Formal charges.
  • VSEPR (no more than four electron pairs about the central atom with the central atom exceeding the "octet rule").
  • Delocalization and resonance.
Inorganic Reactions
  • Combination reactions
  • Decomposition reactions.
  • Precipitation, single and double-replacement reactions.
  • Redox reaction (neutral, alkaline, and acidic).
Nomenclature
  • Main group and transition metal compounds.
Groups 1 and 2
  • Trend in Reactivity of (heavy elements more reactive).
  • Products of reaction (water, halogens, and oxygen).
  • Basicity of oxides.
Groups 13-18 and Hydrogen
  • Binary molecular compounds of hydrogen, formulas, and acid-base properties (CH4, NH3, H2O, H2S).
Group 13
  • The oxidation state of boron and aluminium in their oxides and chlorides is +III.
Group 14
  • Si's oxidation state in its chloride and oxide is +IV.
  • The +II and +IV oxidation states of carbon, tin, and lead.
Group 15
  • Oxides of nitrogen (Reaction of NO to form NO2, dimerization of NO2, Reaction of NO2 with water).
  • Redox properties of nitrogen (HNO3 and nitrates).
Group 16
  • The +IV and +VI oxidation states of sulfur, reaction of their oxides with water, and properties of their acids.
  • Reaction of thiosulfate anion with iodine.
Group 17 (Halogens)
  • Reactivity and oxidant strength decrease from fluorine to iodine.
  • Acid-base properties of the hydrogen halides.
  • The oxidation state of fluorine in its compounds is -I
  • The -I, +I, +III, +V, and +VII oxidation states of chlorine.
  • Reactions of halogens with water.
Group 18
Transition Elements
  • Common oxidation states of common transition metals: Cr(+II), Cr(+III) Mn(+II), Mn(+IV), Mn(+VII) Ag(+I) Fe(+II), Fe(+III), Co(+II), Zn(+I), Cu(+I), Cu(+II), Ni(+II).
  • The insolubility of Ag, Hg, and Cu in HCl.
  • M2+ arising from the dissolution of the other metals in HCl.
  • Permanganate and Dichromate are strong oxidants in acid solution.
Coordination Chemistry
  • Definition of coordination number.
  • Writing equations for complexation reactions given all formulas.
  • Formulas of common complex ions (Ag(NH3)2+, Ag(S2O3)23-,FeSCN+, Cu(NH3)42+).
Organic Chemistry
  • Drawing structures (Condensed Formula, Kekule & Skeletal Structures).
  • DBE (double bond equivalent).
  • Properties, isomerism (structural and stereoisomerism).
  • Substance classes: hydrocarbons (alkane, alkene, alkyne, simple cycloalkane and alkadiene), alcohols, aldehydes, ketones, carboxylic acids, and esters, as well as structure and properties of the substance classes amines, phenols, amides, and amino acids.
  • Types of organic reactions: complete combustion, oxidation, substitution, addition, elimination, condensation, hydrolysis and decarboxylation.
Physical Chemistry
Gas
  • Ideal gas law.
  • Dalton's law.
Thermodynamics
  • First Law (Concept of systems and surroundings, Energy, Heat, and Work).
  • Enthalpy (Relationship between internal energy and enthalpy).
  • Enthalpy is a state property (Hess's law).
  • Reaction enthalpy (use of standard formation enthalpies).
  • Reaction entropy and disorder.
  • Reaction Gibbs energy and definition (ΔG = ΔH – TΔS).
  • Using ΔG to predict the direction and spontaneity.
  • Relationship between Gibbs and equilibrium constant K.
Equilibrium
  • Equilibrium constant (homogeneous and heterogeneous).
  • Reaction quotient (Q/Y).
  • Relating equilibrium constants of pressure (Kp) and concentration (Kc).
  • Le Chatelier's principle.
  • Solubility constant (product) definition (Ksp).
  • Calculation of solubility in water from Ksp.
  • Common-Ion Effect.
  • Complex formation constant (KK)
  • Simple coupled equilibria.
Acid-base
  • Arrhenius definitions of acids and bases.
  • Bronsted-Lowry definitions.
  • Conjugate acids and bases.
  • pH, Kw definition and Ka or Kb as a measure of acid and base strength.
  • Acidity or basicity of ions.
  • Buffer system and capacity.
  • Calculation of pH from pKa (weak acid).
  • Calculation of pH of a simple buffer solution.
  • Simple knowledge of amphoterism and their pH (pH = ½(pKS1+pKS2)).
Chemical Kinetics
  • Factors affecting reaction rate.
  • Reaction coordinates and the basic idea of a transition state.
  • Differential rate laws.
  • Concept of reaction order.
  • Rate constant definition.
  • 0, 1, and 2 order reactions and their integrated rate laws (single reactant).
  • Dependence of concentration on time.
  • Concept of half-life.
  • Relationship between half-life and rate constant.
  • Determine reaction order (method of initial rates and graphs of integrated rate laws).
  • Reaction mechanisms (concept of molecularity, rate-determining step).
  • Basic concepts of collision theory.
  • Arrhenius's law.
  • Catalysts and how it affects activation energies (homogeneous, heterogeneous, and biocatalysts).
Mathematics Skills
  • Solving quadratic equations.
  • Use of logarithms and exponentials.
  • Solving simultaneous equations with 2 unknowns.
  • Elementary geometry such as Pythagorean's theorem.
  • Plotting graphs (normal, exponential, and logarithmic).

Silver Tier Syllabus

As shown in the the table below, a more detailed description can be found about the silver tier syllabus:

Analytical Chemistry
SpectroscopyMass Spectrometry
  • Recognition of molecular ions.
  • Recognition of fragments with the help of a table.
  • Recognition of typical isotope distribution.
x-Ray
  • Bragg's Law.
Infrared
  • Interpretation using a table of frequencies (N-H stretch, O-H stretch, C-H stretch (sp2), C-H stretch (sp3), C=O stretch and C=C stretch).
  • Recognition of hydrogen bonds.
NMR
  • General concepts (chemical shift, integration, spin-spin coupling, and coupling constants).
  • Interpretation of a simple 1H spectrum
  • Identification of o- and p-disubstituted benzene.
  • Interpretation of simple spectra of 13C (proton decoupled) and other ½ spin nuclei.
Titration
  • Complexometric titrations (EDTA).
Inorganic Chemistry
Periodic Trends
  • Transition metal elements (electron configuration, Pauli exclusion principle, Hund’s Rule, electronegativity, electron affinity, first ionization energy, atomic size, ion size, highest oxidation number).
The Atom
  • Shape, orientation, and Quantum numbers (n, l, m) of s, p, and d orbitals.
  • Radial and angular nodes.
Chemical Bonding
  • Valence bond theory (σ-bonds, π-bonds, hybrid orbitals).
  • Molecular orbital (MO) diagram (2 period).
  • Bond orders.
  • Para- and diamagnetism.
Inorganic Reactions
  • Comproportionation and disproportionation reactions.
  • Special bonding (3c-2e) using molecular orbital theory.
Nomenclature
  • Simple metal complexes.
Group 1 and 2
  • Properties of hydrides.
  • Other compounds, properties, and oxidation states.
Group 13-18 and Hydrogen
  • Other properties.
Group 13
  • The acid-base properties of aluminum oxide/hydroxide.
  • Reaction of boron(III) oxide and boron(III) chloride with water.
  • Other compounds, properties, and oxidation states.
Group 14
  • The acid-base and redox properties of the oxides and chlorides.
  • Other compounds, properties, and oxidation states.
Group 15
  • Phosphorus (+III, +V) oxide and chloride, and their reaction with water.
  • Redox properties (HNO2 and NH2NH2).
  • Bi(+V) and Bi(+III).
  • Other compounds, properties, and oxidation states.
Group 16
  • Other compounds, properties, and oxidation states.
Group 17
  • Mononuclear oxoanions of chlorine.
  • Reaction of Cl2O and Cl2O7 with water.
  • Other compounds, properties, and oxidation states.
Group 18
Transition Elements
  • Colors of ions in aqueous solution: : Cr(+II), Cr(+III) Mn(+II), Mn(+IV), Mn(+VII) Ag(+I) Fe(+II), Fe(+III), Co(+II), Zn(+II), Cu(+I), Cu(+II), Ni(+II).
  • Chromium hydroxide and Zinc hydroxide are amphoteric and the other +2 oxides/hydroxides of the metals listed above are basic.
  • pH dependence of products of permanganate acting as oxidants.
  • Interconversion between chromate and dichromate.
  • Other compounds, properties, and oxidation states.
Coordination Chemistry
  • Formulas of other complex ions.
  • Ligand field theory (eg and t2g terms, high/low spin, and color).
  • Color of complex compounds (spectrochemical series).
  • Para and diamagnetic.
  • Isomerism (Structural, Coordination, Linkage, Geometric: cis/trans, planar, octahedra, enantiomers).
Crystallography
  • Unit cell (cubic).
  • Coordination number.
  • Packing type (aba, abc, abcd).
  • Solid structures (metals, NaCl, CsCl, ZnS).
  • Density for metals and salts.
Organic Chemistry
  • IUPAC nomenclature, including E/Z and R/S stereoisomerism.
  • Draw stereochemically unequivocal structures for organic molecules.
  • Account for optical activity and the difference between enantiomers, diastereomers, and meso compounds.
  • Differentiate between SN1/SN2 and E1/E2 reactions.
  • Draw resonance forms for cations and anions.
  • Predict reactivity of organic molecules based on structure, resonance, and inductive effects.
  • Draw reaction mechanisms for simple and polar reactions.
  • Suggest syntheses in one or more steps of simple, organic molecules.
  • Design simple reactions with common functional groups.
  • Apply inorganic reagents for oxidation, reduction, and substitution in synthetic planning.
  • Account for structure and reactivity of carbohydrates, amino acids, lipids, and nucleic acids.
Physical Chemistry
Thermodynamics
  • Born-Haber cycle for ionic compounds.
  • Bond enthalpies (definition and use).
Electrochemistry
  • Electromotive force (definition).
  • Galvanic Cells.
  • Notation of cell diagrams.
  • Standard electrode potential.
  • Nernst equation.
  • Relationship between ΔG and electromotive force.
  • Electrolysis.
  • Corrosion.
Acids and Bases
  • Lewis acids and bases (hard and soft).
  • MCB (not too complex).
  • Bjerrum plot (reading).
Chemical Kinetics
  • Steady-State approximations (maximum of 4 steps, where an equilibrium step counts as 2 steps).
Mathematics skills
  • Use of math skills from the bronze tier to derive simple expressions.
  • Single-variable Calculus (basic derivatives and integrals).
  • Taylor series.
Mathematical equations may be provided for questions.


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