Regulations of the International Chemistry Olympiad
1. Aims of the competition
The International Chemistry Olympiad (IChO) is a competition for students
with the aim of promoting international contacts in chemistry at secondary
school level. It is intended to stimulate the activities of students interested
in chemistry by way of independent and creative solving of chemical problems.
The IChO competitions help to enhance friendly relations among young people
from different countries; they encourage cooperation and international understanding.
2. Organization and Invitation
The IChO is organized every year at the beginning of July in one of the
participating countries by the Education Ministry or another appropriate
institution of the organizing country (hereafter referred to as the organizer).
The organizer is obliged to ensure equal participation of all the delegations,
and to invite all countries participating in previous IChO competitions.
Additionally, it has the right to invite other countries on agreement with
the organizers of two forthcoming IChOs. A country must send observers to
two consecutive Olympiads before it can participate in an IChO. The invitation
to participate in the forthcoming IChO should be sent to countries by the
November preceeding the competition and must contain information concerning
the place and dates of the competition. The invited countries must confirm
their participation in the IChO by the end of the following January.
Each participating country's delegation consists of four competitors and
two accompanying persons (also known as mentors). The competitors must be
students of secondary school age, who have not specialized in chemistry.
The competitors must be passport holders of the country they represent or
they took part in the educational system of this country for more than one
academic year. All participating students in the competition must be under
the age of 20 at the 1. July in the year of the competition.
Training or any other special instruction, that is carried out for a selected
group, of 50 or fewer, containing the IChO team must be no longer than two
The mentors act as members of the International Jury (see section 4). One
mentor is designated as the head of delegation. Mentors must be capable
of translating the text of competition tasks from English into the mother
tongue of the students and be able to judge the set of tasks and correct
the work of their students.
At the discretion of the organizers, countries may include one observer
in their delegation. Countries that are invited by the organizer, and intend
to take part in future Olympiads, may send one observer.
4. International Jury
The International Jury consists of the Chair, the Secretary of the IChO
and the two mentors from the individual delegations. The Chair is nominated
by the organizer. The Chair calls and chairs the meeting of the International
Jury. Resolutions are passed by the International Jury when they are agreed
by a single majority of votes in the presence of at least 75% of the Jury
members. Each participating country has one vote. The Chair has a casting
vote in the event of a tie. The decisions of the International Jury are
The long term work involved in organizing the Olympiads is coordinated by
the Secretariat of the International Chemistry Olympiad, which is headed
by the Secretary of the IChO. The Secretariat reports to the International
Jury and has no right to make any decisions. The seat of the Secretariat
is in the country where the Secretary is resident until decided otherwise
by the International Jury.
The International Jury elects members of the Steering Committee of the IChO.
The Steering Committee provides organizational oversight for the IChO and
proposes items for consideration at the jury sessions. The Steering Committee
has no right to make any decisions about the IChO.
There are three ex- officio members of the Steering Committee: Chair of
the current IChO; Chair of the immediate past IChO; Chair of the immediate
The Committee consists of following elected members: The IChO secretary
(to serve for a three year term); representatives of variety of geographical
areas to serve a two year term (3 from Europe, 1 from Americas, 1 from Pacific
Rim); and 1 - 3 members to be selected by the Steering Committee for their
particular expertise for periods of one year. Members are elected (for no
more than two consecutive terms) by full jury vote. The Steering Committee
elects its own Chair.
The International Jury may form working groups to solve specific chemistry
related problems of the IChO. This working group should draw its membership
from IChO participating countries and those interested in IChO competitions.
The working groups meet for working sessions and submit the results of the
deliberations to the Steering Committee.
There is an Information Office of IChO, gathering and providing (when necessary)
all the documentation of the IChOs from the very beginning of the Olympiad
to the present. The seat of the Office is in Bratislava, Slovakia.
5. Responsibilities of the International Jury
The International Jury:
- is in charge of the actual competition and its supervision according to
- discusses in advance the competition tasks presented by the organizer, their
solutions and the marking guidelines, gives comments and decides in case
of changes. The members of the International Jury are obliged to maintain
a professional discretion about any relevant information they receive during
the IChO and must not assist any participant;
- supervises the marking of the examination papers and guarantees that all
participants are judged by equal criteria. The members of the International
Jury keep the marking and results secret until proclaimed by the Jury;
- determines the winners and decides on prizes and documents for the competitors;
- monitors the competition and suggests changes to the regulations, organization
and contents for future IChOs.
The competition consists of two parts. Part one, the practical (experimental)
competition takes place before part two, the theoretical competition. A
working time of four to five hours is allotted for each part. There is at
least one day of rest between the two parts. Competitors receive all the
relevant information written in the language of their choice and are allowed
to write the solutions in that language. Only non- programmable pocket calculators
may be used for the solution of the tasks.
The safety regulations announced by the organizer are binding for all participants
(see section 13).
7. Official Language
The working language of the International Jury is English.
The organizer is responsible for the preparation of competition tasks by
competent experts/authors, who constitute the Scientific Board of the IChO.
They propose the methods of solution and the marking scheme. The tasks,
their solutions and the marking schemes are submitted to the International
Jury for consideration and approval. The authors of the tasks should be
present during the discussion. The Chair of the International Jury may put
the Chair of the Scientific Board in charge of the proceedings when the
tasks are considered.
One year in advance of the competition the organizer distributes to all
participating countries a set of about 50 preparatory tasks written in English.
The preparatory tasks must be devised so that students can get a good idea
of the type and difficulty of the competition tasks, including safety aspects
(see section 13 and appendix "B"). According to appendix "C" topics of group
3 must be covered in the preparatory problems. SI units must be used throughout
9. Correcting and Marking
A maximum of 60 points is allocated to the theoretical tasks and 40 points
to the practical tasks, making a total of 100 points. Consequential marking
should be used when correcting the tasks so that students are not punished
twice for the same error. The competition tasks are corrected independently
by the authors and by the mentors. The international Jury discusses the
results and decides on the final scores. The organizer retains the original
10. Results and Prizes
Official results of the competition and the number of medals awarded are
decided by the International Jury. The number of gold medals awarded is
in the range of 8% to 12%, silver 18% to 22%, and bronze medals 28% to 32%
of the total number of competitors. The exact number of medals is decided
by the International Jury on the basis of an anonymous review of the results.
In addition to the medals other prizes may be awarded. Each participant
receives a certificate of participation. No team classification takes place.
In the awarding ceremony, the non medallists are called in alphabetical
order of the countries.
A "Honourable mention" is awarded to students who do not receive a medal,
but gain full marks for any one problem.
The organizer must provide a complete list of results as a part of the final
11. Obligations of the Organizer
The organizer provides:
- the itinerary of the IChO;
- the organisation of the competition following the regulations;
- the medals, certificates and prizes, which are presented at the official
- translation and interpreting facilities;
- arrangement for the observance of the safety regulations;
- accident insurance for all participants in connection with the organized
- the opportunity for the International Jury to inspect the working room and
practical apparatus to be used for the practical tasks before the competition
- a printed report on the competition to be distributed not later than six
months after the competition;
- transportation from/to an airport decided by the host country on the day
of arrival and departure.
The participating country covers the return travel costs of the students
and the accompanying persons to the designed airport or to the place at
which the competition is held. All other costs in connection with the organized
programme, including the costs of accommodation and pocket money for all
competitors and members of the International Jury, are covered by the organizer.
The organizer of the next Olympiad may send two observers to the current
IChO with their expenses covered by the host.
During the experimental part, the competitors must wear laboratory coats
and eye protection. The competitors are expected to bring their own laboratory
coats. Other means of protection for laboratory work are provided by the
organizer. Pipetting by mouth is strictly forbidden. When handling liquids,
each student must be provided with a pipette ball or filler.
The use of very toxic substances (designation T+) is strictly forbidden.
The use of toxic substances (designation T) is not recommended, but may
be allowed if special precautions are taken. Substances belonging to the
categories R 45, R 46, R 47 must not be used under any circumstances. (See
appendix "B" for definitions of these categories.)
The organizer shall provide a list of chemicals from which the chemicals
used in practical preparatory and competition tasks will be drawn. The list
of chemicals must include information of the maximum amounts of materials
needed or in the case of solutions their maximum concentrations. Any hazardous
materials on the list must be accompanied by detailed instructions for safe
handling. The list must be provided - together with the preparatory tasks
(see section 8) - one year in advance.
Each participating country has three months to file a substantiated dissent
concerning the use of a special chemical. Silence indicates acceptance.
The organizer should try to revise the list in order to satisfy any objections.
The final revision of the list will be distributed to the delegation leaders
at the start of the Olympiad.
Detailed recommendations involving students' safety and the handling and
disposal of chemicals can be found in
Appendix A 1: "Safety Rules for Students in the laboratory" and
Appendix A 2: "Safety Rules and Recommendations for the Host Country of
Appendix B contains:
- B 1: Hazard Warning Symbols and Hazard Designations;
- B 2: R- Ratings and S- Provisions: Nature of special risks (R) and safety
- B 3: Explanation of Danger Symbols (for use of chemicals in schools);
- B 4: Basic List of Chemicals.
14. Final Regulations
Those who take part in the competition acknowledge these regulations through
their very participation.
Changes in these regulations can only be made by the International Jury
and require a qualified majority (two thirds of the votes).
These regulations of the IChO were approved by the International Jury in
Oslo (Norway) on July 7, 1994.
A 1: Safety Rules for Students in the Laboratory
"Paracelsus (a middle European medical scientist) recognized as long ago
as the l5th century that all materials are toxic at some level. Only dosage
separates the medicament from the poison (except for sensitization and allergic
reactions). Indeed, practically any substance can be harmful, so there are
also degrees of being safe. A complex relationship exists between a material
and its biological effect in humans that involves considerations of dose
(the amount of a substance to which one is exposed), the length of time
of the exposure, the route of exposure (inhalation, ingestion, absorption
through the skin), and myriad other factors such as sex, stage in the reproductive
cycle, age, race, and even lifestyle. Because of the many factors influencing
toxicity, all chemicals should be handled with respect for their known or
The above passage is quoted from the 1985 version of the booklet entitled
Safety in Academic Laboratories, published by the American Chemical Society.
It is the nature of the profession that chemists must deal with chemicals.
All students of chemistry must recognize that hazardous materials cannot
be completely avoided. Chemists must learn to handle all materials in an
appropriate fashion. While it is not expected that all students participating
in the International Chemistry Olympiad know the hazards of every chemical,
the organizers of the competition will assume that all participating students
know the basic safety procedures (as an example of such a safety procedure,
the organizers will assume that students know never to eat, drink or smoke
in the laboratory or taste a chemical).
In addition to the common- sense safety considerations to which students
should have been previously exposed, some specific rules, listed below,
must also be followed during the Olympiad. If any question arises concerning
safety procedures during the practical exam, the student should not hesitate
to ask the nearest supervisor for direction.
Rules regarding personal protection
- Eye protection must be worn in the laboratories at all times. If the student
wears contact lenses, full protection goggles must also be worn. Eye protection
will be provided by the host country.
- A laboratory coat is required. Each student will supply this item for himself/herself.
- Long pants and closed- toed shoes are recommended for individual safety.
Long hair and loose clothing should be confined.
- Pipetting by mouth is strictly forbidden. Each student must be provided
with a pipette bulb or pipette filler.
Rules for Handling Materials
- Specific instructions for handling hazardous materials will be included
by the host country in the procedures of the practical exam. All potentially
dangerous materials will be labelled using the international symbols below.
Each student is responsible for recognizing these symbols and knowing their
meaning (see Appendix B 1, B 2 and B 3).
- Do not indiscriminately dispose chemicals in the sink. Follow all disposal
rules provided by the host country.
A 2: Safety Rules and Recommendations for the Host Country of the IChO
Certainly it can be assumed that all students participating in the IChO
have at least modest experience with laboratory safety procedures. However
it is the responsibility of the International Jury and the organizing country
to be sure that the welfare of the students is carefully considered. Reference
to the Safety Rules for Students in the Laboratory will show that the students
carry some of the burden for their own safety. Other safety matters will
vary from year to year, depending on practical tasks. The organizers of
these tasks for the host country are therefore assigned responsibility in
the areas listed below. The organizers are advised to carefully test the
practical tasks in advance to ensure the safety of the experiments. This
can best be accomplished by having students of ability similar to that of
IChO participants carry out the testing.
Rules for the Host Country (see also A 1):
- Emergency first- aid treatment should be available during the practical
- Students must be informed about the proper methods of handling hazardous
- Specific techniques for handling each hazardous substance should be included
in the written instructions of the practical examination.
- All bottles (containers) containing hazardous substances must be appropriately
labelled using international symbols (see Appendix B 1).
- Chemical disposal instructions should be provided to the students within
the written instructions of the practical examination. Waste collection
containers should be used for the chemicals considered dangerous to the
- The practical tasks should be designed for appropriate (in other words,
minimum) quantities of materials.
- The laboratory facilities should be chosen with the following in mind:
- Each student should not only have adequate space in which to work, but should
be in safe distance from other students.
- There should be adequate ventilation in the rooms and a sufficient number
of hoods when needed.
- There should be more than one emergency exit for each room.
- Fire extinguishers should be near by.
- Electrical equipment should be situated in an appropriate spot and be of
a safe nature.
- There should be appropriate equipment available for spill clean- up.
- It is recommended that one supervisor be available for every four students
in the laboratory to adequately ensure safe conditions.
- The organizers should follow international guidelines for the use of toxic,
hazardous or carcinogenic substances in the IChO.
B 1 : Hazard warning symbols and hazard designations
E O Explosive Oxidising F+ F Highly flammable Easily flammable T+ T Xn Highly
toxic Toxic Harmful C Xi Corrosive Irritant
Explanation of danger symbols see Appendix B 3
B 2 : R-Ratings and S-Provisions
Nature of special risks (R)
- R 1 Explosive when dry.
- R 2 Risk of explosion by shock friction, fire or other sources of ignition.
- R 3 Extreme risk of explosion by shock friction, fire or other sources of
- R 4 Forms very sensitive explosive metallic compounds.
- R 5 Heating may cause an explosion.
- R 6 Explosive with or without contact with air.
- R 7 May cause fire.
- R 8 Contact with combustible material may cause fire.
- R 9 Explosive when mixed with combustible material.
- R 10 Flammable.
- R 11 Highly flammable.
- R 12 Extremely flammable.
- R 13 Extremely flammable liquefied gas.
- R 14 Reacts violently with water.
- R 15 Contact with water liberates highly flammable gases.
- R 16 Explosive when mixed with oxidizing substances.
- R 17 Spontaneously flammable in air.
- R 18 In use, may form flammable/explosive vapour-air mixture.
- R 19 May form explosive peroxides.
- R 20 Harmful by inhalation.
- R 21 Harmful in contact with skin.
- R 22 Harmful if swallowed.
- R 23 Toxic by inhalation.
- R 24 Toxic in contact with skin.
- R 25 Toxic if swallowed.
- R 26 Very toxic by inhalation.
- R 27 Very toxic in contact with skin.
- R 28 Very toxic if swallowed.
- R 29 Contact with water liberates toxic gas.
- R 30 Can become highly flammable in use.
- R 31 Contact with acids liberates toxic gas.
- R 32 Contact with acids liberates very toxic gas.
- R 33 Danger of cumulative effects.
- R 34 Causes burns.
- R 35 Causes severe burns.
- R 36 Irritating to eyes.
- R 37 Irritating to respiratory system.
- R 38 Irritating to skin.
- R 39 Danger of very serious irreversible effects.
- R 40 Possible risks of irreversible effects.
- R 41 Danger of serious eye damage.
- R 42 May cause sensitization by inhalation.
- R 43 May cause sensitization by skin contact.
- R 44 Risk of explosion if heated by occlusion.
- R 45 May cause cancer.
- R 46 May cause hereditary damage.
- R 47 May cause embryo damage.
- R 48 Danger of chronic damage.
Safety advice (S)
- S 1 Keep locked up.
- S 2 Keep out of reach of children.
- S 3 Keep in a cool place.
- S 4 Keep away from living quarters.
- S 5 Keep contents under .... (appropriate liquid to be specified by the
- S 6 Keep under .... (inert gas to be specified by the manufacturer).
- S 7 Keep container tightly closed.
- S 8 Keep container dry.
- S 9 Keep container in a well- ventilated place.
- S 10 Keep contents wet.
- S 11 Avoid contact with air.
- S 12 Do not keep the container sealed.
- S 13 Keep away from food, drink and animal feeding stuffs.
- S 14 Keep away from .... (incompatible materials to be indicated by the
- S 15 Keep away from heat.
- S 16 Keep away from sources of ignition - No smoking.
- S 17 Keep away from combustible materials.
- S 18 Handle and open container with care.
- S 20 When using do not eat or drink.
- S 21 When using do not smoke.
- S 22 Do not inhale dust.
- S 23 Do not inhale gas/fumes/vapour/spray.
- S 24 Avoid contact with skin.
- S 25 Avoid contact with eyes.
- S 26 In case of contact with eyes, rinse immediately with plenty of water
and seek medical advice.
- S 27 Take off immediately all contaminated clothing.
- S 28 After contact with skin, wash immediately with plenty of (to be specified
by the manufacturer).
- S 29 Do not empty into drains.
- S 30 Never add water to this product.
- S 31 Keep away from explosive materials.
- S 33 Take precautionary measures against static discharges.
- S 34 Avoid shock and friction.
- S 35 This material and its container must be disposed of in a safe way.
- S 36 Wear suitable protective clothing.
- S 37 Wear suitable gloves.
- S 38 In case of insufficient ventilation, wear suitable respiratory equipment.
- S 39 Wear eye/face protection.
- S 40 To clean the floor and all objects contaminated by this material, use
.... (to be specified by the manufacturer).
- S 41 In case of fire and/or explosion do not breathe fumes.
- S 42 During fumigation/spraying wear suitable respiratory equipment.
- S 43 In case of fire, use (indicate in space the precise type of fire- fighting
equipment. If water increases the risk, add - Never use water).
- S 44 If you feel unwell, seek medical advice (show the label where possible).
- S 45 In case of accident or if you feel unwell, seek medical advice (show
the label where possible).
B 3: Explanation of Danger Symbols (for Chemicals in Schools)
(see B 1)
1. Explosive substances /E/
These are substances which can be caused to explode by exposure to a flame
or which are more sensitive to impact or friction than 1,3- Dinitrobenzene
(e.g. picrates, organic peroxides). In particular they include substances
with R- ratings R I - R 3 (see B 2), designation E.
When using and storing these substances, the S- provisions (S 15 - S 17)
must be observed (see B 2).
2. Fire- inducing substances, Oxidizing /O/
These are substances which can have a strong exothermic reaction on coming
into contact with other, particularly flammable substances or organic peroxides.
They include in particular substances R 7 to R 9, designation O.
3. Highly flammable, easily flammable and flammable substances /F+, F/
In liquid form, highly flammable substances have an ignition point below
0deg.C and a boiling point of 35deg.C maximum. They are to be designated
by the danger symbol F+ and the rating R 12.
Substances are easily flammable if they
- can heat up and ignite at normal air temperature without energy supply,
- are easily ignited in solid state by short exposure to a source of flammation
and continue to burn or glow after removal of the latter,
- ignite below 21deg.C in liquid state,
- ignite in gaseous state if mixed with air at 1013 hPa and 20deg.C,
- develop easily flammable gases in dangerous quantities when in contact with
water or damp air,
- ignite if brought into contact with air when in dustlike state. These substances
are to be designated with the danger symbol F and the rating R 11.
Flammable substances have in liquid form an ignition point of 21deg.C to
55deg.C and are to designated with the rating R 10, no danger symbol.
When dealing with highly flammable, easily flammable and flammable liquids,
these may only be heated using sealed electrical heating equipment which
is not in itself a source of flammation. All substances must be heated in
such a way that the dangerous vapours liberated by heating cannot escape
into the atmosphere. This does not apply to fire- hazardous substances in
small quantities for fire demonstrations.
The regulations laid down by the state fire authorities must be observed.
4. Toxic substances /T+, T, Xn/
Legislation applying to chemicals distinguishes three categories of toxicants:
- - highly toxic substances (R 26 - R 28), danger symbol T+,
- - toxic substances (R 23 - R 25), danger symbol T,
- - less toxic substances (R 20 R 22), danger symbol Xn,.
Highly toxic substances are those which can cause grave acute or chronic
health damage or death almost immediately if inhaled, swallowed or absorbed
through the skin in small amounts.
Toxic substances are those which can cause considerable acute or chronic
health damage or death if inhaled, swallowed or absorbed through the skin
in small amounts.
Less toxic substances (noxious substances) are those which can cause restricted
health damage if inhaled, swallowed or absorbed through the skin.
If highly toxic or toxic substances are produced in the course of an experiment
(e.g. chlorine, hydrogen sulfide), these may only be produced in the quantities
necessary for the experiment. In the case of volatile substances, the experiment
must be conducted under a hood where the gas can be drawn off. Residue must
be appropriately disposed of after the experiment and may on no account
be stored. If the facilities for disposal are not available, the experiment
may not be conducted.
Less toxic substances and preparations may be obtained without a permit.
Less toxic substances are also those which contain a highly toxic or toxic
substance at a level of concentration below that determined by law as the
maximum for classification as noxious. Chlorine water, bromine water and
hydrogen sulfide solution in a concentration of up to 1% may therefore be
used in instruction.
5. Corrosives and irritants /C, Xi/
Caustic or corrosive substances (R 34, R 35), designation C, are those which
can destroy living materials by their action upon it. Substances are classed
as irritants (R 36 - R 38), designation Xi, if they cause inflammation -
without being corrosive - on direct, prolonged or repeated contact with
the skin or mucous membranes. The relevant safety recommendations (S 22
- S 28) should be observed.
6. Carcinogenic, genotype or embryo- damaging, chronically harmful substances
Substances may not be used for instruction if they have a proven carcinogenic
effect (R 45), if they cause hereditary damage (R 46) or embryo damage (R
47), or if they are chronically damaging (R 48), particularly those substances
classed as unmistakably carcinogenic. Such substances must be removed from
all school stocks. Storage is not permitted under any circumstances.
Further, substances for which there is a well- founded suspicion of carcinogenic
potential (R 40) may only be used if corresponding safety precautions are
taken and only in such cases where they cannot be replaced by less dangerous
B 4: Basic list of chemicals
Acetic acid Hydrochloric acid
Acetic acid anhydride Hydrogen peroxide (aq)
Aluminium chloride 2-Hydroxy-naphthalene
Aluminium nitrate Iodine
Aluminium oxide Iron
Aluminium sulfate Iron(II,III) oxide
Amino acids (natural) Iron(II) ammonium sulfate
4-Aminobenzoic acid Iron(II) sulfate
1-Amino-naphthalene Iron(III) chloride
Ammonia (aq) Iron(III) oxide
Ammonium carbonate Lead chloride
Ammonium chloride Lead dioxide
Ammonium nitrate Lead monoxide
Ammonium oxalate Lead nitrate (aq)
Ammonium sulfate Lead oxide (red)
Ammonium thiocyanate Magnesium
Barium chloride Magnesium chloride
Barium hydroxide (aq) Magnesium nitrate
Barium nitrate Magnesium sulfate
Benzaldehyde Manganese dioxide
Benzoic acid Manganese(II) nitrate
Benzophenone Manganese(II) sulfate
Bismuth trichloride Methanal
Bromine (aq) Methanol
Bromocresol green Methyl orange
Bromothymol blue Methyl-2-propanol
Butanone N,N-Dimethyl formamide
Calcium carbonate Natural fatty acids
Calcium chloride Nickel chloride
Calcium hydroxide (aq) Nickel sulfate
Calcium nitrate Nitric acid
Calcium sulfate Oxalic acid
Carbon (activated) Phenol
Chromium(III) chloride (aq) Phenolphthalein
Chromium(III) nitrate (aq) Phosphorous pentoxide
Cobalt chloride Phosphoric acid
Copper(I) chloride Phthalic acid anhydride
Copper(I) oxide Potassium aluminium sulfate
Copper(II) chloride Potassium bromate
Copper(II) oxide Potassium chloride
Copper(II) sulfate Potassium chromate (aq)
Cyclohexane Potassium cyanoferrate(II)
Cyclohexanol Potassium cyanoferrate(III)
Cyclohexanone Potassium dichromate (aq)
Cyclohexene Potassium hydrogensulfate
Diethylether Potassium hydroxide
1,2-Dihydroxybenzene Potassium iodate
1,3-Dihydroxybenzene Potassium iodide
1,4-Dihydroxybenzene Potassium nitrate
2,4-Dinitrophenyl-hydrazine Potassium orthophosphate
Ethanal Potassium permanganate
1,2-Ethanediol Potassium sodium tartrate
Ethanol Potassium sulfate
Ethyl acetate Potassium sulfite
EDTA (+ indicators) Potassium thiocyanate
Formic acid Propanetriol
Propanone Sodium sulfide
Salicylic acid Sodium sulfite
Silver nitrate Sodium tetraborate decahydrate (Borax)
Silver sulfate Sodium thiosulfate
Sodium acetate Starch
Sodium bromate Strontium nitrate
Sodium bromide Sucrose
Sodium carbonate Sulfur
Sodium chlorate Sulfuric acid
Sodium chlorate(I) (aq) Tartaric acid
Sodium chloride 1,1,2,2-Tetrachloro-ethane
Sodium fluoride Tin
Sodium hydrogencarbonate Tin(II) chloride
Sodium hydrogensulfite Toluene
Sodium iodide 1,1,1-Trichloroethane
Sodium nitrate Urea
Sodium nitrite Xylene
Sodium orthophosphate Zinc
Sodium orthophosphate mono-H Zinc chloride
Sodium orthophosphate di-H Zinc oxide
Sodium oxalate Zinc sulfate
Classification of the chemical topics
- Group 1:
- These topics are included in the overwhelming majority of secondary school
- Group 2:
- These topics are included in a substantial number of secondary school programs;
however, if not covered, it would be expected that the Olympiad level students
from every country would have been introduced to these topics.
- Group 3:
- These topics are not included in the majority of secondary school programs.
For a host nation it is no longer necessary to have preparatory problems
on Group 1 and Group 2 topics, although, in the latter case, a listing of
the specific topics of that Group which might be part of the Olympiad Examination
is to be given by the host nation. Any topics in Group 3 which might appear
on the Olympiad Examination must be covered in the preparatory problems.
- main groups 1
- transition metals 2
- lanthanide and actinide metals 3
- Pauli exclusion Principle 1
- Hund's Rule 1
TRENDS IN THE PERIODIC TABLE (MAIN GROUPS)
- electronegativity 1
- electron affinity 2
- first ionization energy 2
- atomic size 1
- ionic size 2
- highest oxidation number 1
TRENDS IN PHYSICAL PROPERTIES (MAIN GROUPS)
- melting point 1
- boiling point 1
- metal character 1
- magnetic properties 2
- thermal properties 3
- metal structures 3
- ionic crystal structures 3
- simple molecular structures with central atom
- exceeding the octet rule 3
- stereochemistry 3
- main group compounds 1
- transition metal compounds 1
- simple metal complexes 2
- multicenter metal complexes 3
- coordination number 1
- balancing equations 1
- mass and volume relationships 1
- empirical formula 1
- Avogadro number 1
- concentration calculations 1
- counting of nucleons 1
- radioactive decay 1
- nuclear reaction (alpha, beta, gamma, neutrino) 2
- nitrogen 2
- oxygen 2
- carbon 2
- products of reaction of group I and II metals with water, basicity of the
- products of reaction of the metals with halogens 1
- products of reaction of the metals with oxygen 2
- heavier elements are more reactive 1
- Li combine with H2 and N2, forming LiH and Li3N 2
- stoichiometry of simplest nonmetal hydrides 1
- properties of metal hydrides 3
- acid/base properties of CH4, NH3, H2S, H2O, HX 1
- NO react with O2 to form NO2 1
- there is equilibrium between NO2 and N2O4 1
- products of reaction of NO2 with water 1
- HNO2 and it's salts are reductors 1
- HNO3 and it's salts are oxidants 1
- N2H4 is a liquid and reductor 3
- there exists acids like H2N2O2, HN3 3
- to remember, what are products of reduction of nitrates or HNO3 with different metals and reductors 3
- reaction of Na2S2O3 with iodine 2
- other tioacids poyacids, peroxoacids 3
- B(III), Al(III), Si(IV), P(V) S(IV), S(VI), O(II), F(I), Cl(I) Cl(III),
Cl(V) and Cl(VIII) are normal oxidation states of 2nd and 3rd row elements
in compounds with halogens and in oxoanions 1
- compounds of nonmetals with other oxidation stales 3
- the preferred oxidation states are Sn(II), Pb(II), Bi(III) 2
- products of reactions of nonmetal oxides with water and stoichiometry of
resulting acids 1
- reactions of halogens with water 2
- reactivity and oxidizing power of halogens decrease from F2 to I2 1
- differences of chemistry between row 4 and row 3 elements 3
- common oxidation states of the common d- block metals are Cr(III), Cr(VI),
Mn(II), Mn(IV), Mn(VII), Fe(II), Fe(III), Co(II), Ni(II), Cu(I), Cu(II),
Ag(I), Zn(II), Hg(I), Hg(II) 1
- colors of the listed common ions in aqueous solution 2
- other oxidation stales and chemistry of other d- block elements 3
- Cr, Mn, Fe, Ni, Co, Zn dissolve in dil HCI; Cu, Ag, Hg do not dissolve 1
- products of the dissolution are (2+) cations 2
- passivation of Cr, Fe (and also Al) 2
- Cr(OH)3 and Zn(OH)2 are amphoteric, other common hydroxides are not 1
- MnO4-, CrO42-, Cr2O72- are strong oxidants 1
- products of reduction of MnO4- depending on pH 2
- polyanions other than Cr2O72- 3
OTHER INORGANIC PROBLEMS
- industrial production of H2SO4, NH3, Na2CO3, Na, Cl2, NaOH 1
- chemistry of lanthanides and actinides 3
- chemistry of noble gases 3
- isomers of butane 1
- naming (IUPAC) 1
- trends in physical properties 1
- substitution (eg with Cl2)
- - products 1
- - free radicals 2
- - initiation/termination of the chain reaction 2
- - names 1
- - strain in small rings 2
- - chair/boat conformation 2
- planarity 1
- E/Z (cis/trans) isomerism 1
- addition of Br2, HBr - products 1
- - Markovnikoff rule 2
- - carbonium ions in addition reaction 3
- - relative stability of carbonium ions 3
- - 1,4- addition to alkadiene 3
- linear geometry 1
- acidity 2
- formula of benzene 1
- delocalization of electrons 1
- stabilisation by resonance 1
- Huckel (4n+2) rule 3
- aromaticity of heterocycles 3
- nomenclature (IUPAC) of heterocycles 3
- polycyclic aromatic compounds 3
- effect of first substituent: - on reactivity 2
- - on direction of substitution 2
- explanation of substituent effects 2
- hydrolysis reactions 2
- exchange of halogens 3
- reactivity (primary vs secondary vs tertiary) 2
- ionic mechanism 2
- side products (elimination) 2
- reactivity (aliphatic vs aromatic) 2
- Wurtz (RX + Na) reaction 3
- halogen derivatives & pollution 3
- hydrogen bonding - alcohols vs ethers 1
- acidity of alcohols vs phenols 2
- dehydration to alkenes 1
- dehydration to ethers 2
- esters with inorganic acids 2
- iodoform reaction 2
- reactions of primary/sec./tert. :Lucas reagent 2
- formula of glycerin 1
- nomenclature 1
- keto/enol tautomerism 2
- preparation - oxidation of alcohols 1
- - from carbon monoxide 3
- reactions: - oxidation of aldehydes 1
- - reduction with Zn metal 2
- - addition of HCN 2
- of NaHSO3 2
- of NH2OH 2
- - aldol condensation 3
- - Cannizzaro (PhCH20H disproportionation) 3
- - Grignard reaction 2
- - Fehling (Cu2O) and Tollens (Ag mirror) 2
- inductive effect and strength 2
- equivalence of oxygen atoms in anions 2
- preparation: - from esters 2
- - from nitriles 2
- products of reaction with alcohols (esters) 1
- mechanism of esterification 2
- isotopes in mechanism elucidation 3
- nomenclature: acid halides 2
- preparation of acid chlorides 2
- amides from acid chlorides 2
- nitriles from acid chlorides 3
- properties & preparation of anhydrides 2
- oxalic acid: name and formula 1
- multifunctional acids 2
- optical activity (eg. lactic acid) 2
- R/S nomenclature 3
- plant vs animal fats - differences 2
- amines are basic 1
- comparing aliphatic vs aromatic 2
- names: primary, secondary, tertiary, quaternary 2
- identif. of primary/sec/tert/quatern. in lab. 3
- preparation of amines
- - from halogen compounds 2
- - from nitro compounds (PhNH2 from PhNO2) 3
- - from amides (Hoffmann) 3
- mechanism of Hoffmann r. in acidic/basic medium 3
- basicity amines vs amides 2
- diazotation products
- - of aliphatic amines 3
- - of aromatic amines 3
- dyes: color vs structure (chromophore groups) 3
- nitrocompounds: aci/nitro tautomerism 3
- Beckmann (oxime - amide) rearrangements 3
SOME LARGE MOLECULES
- hydrophilic/hydrophobic groups 2
- micelle structure 3
- preparation of soaps 1
- products of polymerization of
- - styrene 2
- - ethene 1
- - polyamides 3
- - phenol + aldehydes 3
- - polyurethanes 3
- polymers - cross- linking 3
- - structures (isotactic etc) 3
- - chain mechanism of formation 2
- rubber composition 3
AMINO ACIDS AND PEPTIDES
- ionic structure of aminoacids 1
- isoelectric point 2
- 20 aminoacids (classification in groups) 2
- 20 aminoacids (all structures) 3
- ninhydrin reaction (incl. equation) 3
- separation by chromatography 3
- separation by electrophoresis 3
- peptide linkage 1
- primary structure of proteins 1
- -S-S- bridges 3
- sequence analysis 3
- secondary structures 3
- details of alpha- helix structure 3
- tertiary structure 3
- denaturation by change of pH, temp., metals, EtOH 2
- quaternary structure 3
- separation of proteins (molecule size and solubility) 3
- metabolism of proteins (general) 3
- proteolysis 3
- transamination 3
- four pathways of catabolism of amino acids 3
- decarboxylation of amino acids 3
- urea cycle (only results) 3
FATTY ACIDS AND FATS
- IUPAC names from C4 to C18 2
- trival names of most important (ca 5) f.acids 2
- general metabolism of fats 3
- beta- oxidation of fatty acids (formulas & ATP balance) 3
- fatty acids & fats anabolism 3
- phosphoglycerides 3
- membranes 3
- active transport 3
- general properties, active centres 2
- nomenclature, kinetics, coenzymes, function of ATP etc 3
- glucose and fructose:chain formulas 2
- - Fischer projections 2
- - Haworth formulas 3
- osazones 3
- maltose as reducing sugar 2
- difference between starch & cellulose 2
- difference between alpha- and beta-D glucose 2
- metabolism from starch to acetyl- CoA 3
- pathway to lactic acid or to ethanol;
- catabolism of glucose 3
- ATP balance for these pathways 3
- photosynthesis (products only) 2
- light and dark reaction 3
- detailed Calvin cycle 3
KREBS CYCLE AND RESPIRATION CHAIN
- formation of CO2 in the cycle (no details) 3
- intermediate compounds in the cycle 3
- formation of water and ATP (no details) 3
- FMN and cytochromes 3
- calculation of ATP amount for 1 mol glucose 3
NUCLEIC ACIDS AND PROTEIN SYNTHESES
- pyrimidine, purine 2
- nucleosides, nucleotides 3
- formulas of all pyrimidine and purine bases 3
- difference between ribose and 2- deoxyribose 3
- base combination CG and AT 3
- - "- (hydrogen bonding structures) 3
- difference between DNA and RNA 3
- difference between mRNA and tRNA 3
- hydrolysis of nucleic acids 3
- semiconservative replication of DNA 3
- DNA-ligase 3
- RNA synthesis (transcription) without details 3
- reverse transcriptase 3
- use of genetic code 3
- start and stop codons 3
- translation steps 3
- hormones, regulation 3
- hormone feedback 3
- insulin, glucagon, adrenaline 3
- mineral metabolism (no details) 3
- ions in blood 3
- buffers in blood 3
- haemoglobin: function & skeleton 3
- - diagram of oxygen absorption 3
- steps of clotting the blood 3
- antigens and antibodies 3
- blood groups 3
- acetyl choline structure and functions 3
INSTRUMENTAL METHODS OF DETERMINING STRUCTURE
- identification of aromatic compound 3
- identification of chromophore 3
- recognition of: - molecular ion 3
- - fragments with a help of a table 3
- - typical isotope distribution 3
- interpretation using a table of group frequencies 3
- recognition of hydrogen bonds 3
- Raman spectroscopy 3
- interpret. of simple spectrum (like ethanol) 3
- spin- spin coupling 3
- coupling constants 3
- identification of o- and p- substituted benzene 3
- 13C- NMR 3
- Bragg law 3
- electron density diagrams 3
- coordination number 3
- unit cell 3
- structures of:
- - NaCl 3
- - CsCl 3
- - close- packed (2 types) 3
- determining of the Avogadro constant from X- ray data 3
- calculation of specific rotation angle 3
- dynamical model of chemical equilibrium 1
- chemical equilibrium expressed in terms of
- - relative concentration 1
- - relative partial pressures 2
- the relationship between equilibrium constant for ideal gases expressed
in different ways (concentrations, pressures, mole fractions) 2
- relation of equilibrium constant and standard Gibbs energy 3
- Arrhenius theory of acids and bases 1
- Broensted-Lowry theory, conjugated acids & bases 1
- definition of pH 1
- ionic product of water 1
- relation between Ka, and Kb for conjug acids & bases 1
- hydrolysis of salts 1
- solubility product - definition 1
- calcul. of solubility (in water) from solubility product 1
- calcul. of pH for weak acid from Ka, 1
- calcul. of pH for 10- 7 mol/dm3 HCI 2
- calcul. of pH for multiprotic acids 2
- definition of activity coefficient 2
- definition of ionic strength 3
- Debye- Hueckel formula 3
- electromotive force (definition) 1
- first kind electrodes 1
- standard electrode potential 1
- Nernst equation 2
- second kind electrodes 2
- relation between [[Delta]]G and electromotive force 3
KINETICS OF HOMEGENOUS REACTION
- factors influencing reaction rate 1
- rate equation 1
- rate constant 1
- order of reaction 2
- 1st order reactions: time dependence of concentration 2
- - half life 2
- - relation between half-life and rate const 2
- rate- determining step 2
- molecularity 2
- Arrhenius equation, activation energy (defin.) 2
- calculation of rate constant for 1st order reactions 2
- calculation of rate constant for 2, 3 order reactions 3
- calculation of activation energy from experim. data 3
- basic concepts of collision theory 3
- basic concepts of transition state theory 3
- opposing, parallel and consecutive reactions 3
- system and its surroundings 2
- energy, heat and work 2
- relation between enthalpy and energy 2
- heat capacity - definition 2
- difference between Cp and Cv 3
- Hess law 2
- Born- Haber cycle for ionic compounds 3
- lattice energies - approximate calculations
- (e.g.Kapustinski equation) 3
- use of standard formation enthalpies 2
- heats of solution and solvation 2
- bond energies - definition and uses 2
- Entropy - definition (q/T) 2
- entropy and disorder 2
- relation S=k ln W 3
- relation G = H - T S 2
- [[Delta]]G and directionality of changes 2
- ideal gas law 1
- van der Waals gas law 3
- definition of partial pressure 1
- Temp.dependence of the vapour pressure of liquid 2
- Clausius-Clapeyron equation 3
- reading phase diagram: triple point 3
- - critical temperature 3
- liquid- vapour system (diagram) 3
- - ideal and nonideal systems 3
- - use in fractional distillation 3
- Henry's law 2
- Raoult's law 2
- deviations from Raoult law 3
- Boiling point elevation law 2
- freezing- point depression, determ. of molar mass 2
- osmotic pressure 2
- partition coefficient 3
- solvent extraction 2
- basic principles of chromatography 2
- using pipette 1
- using burette 1
- choice of indicators for acidimetry 1
- titration curve: pH (strong AND weak acid) 2
- - EMF (redox titration) 2
- calcul. of pH of simple buffer solution 2
- identification of: Ag+, Ba2+, Cl- , SO42- ions 1
- - of Al3+, NO2- , NO3- , Bi3+ ions 2
- - of VO3- , CIO3- , Ti4+ ions 3
- - using flame test for K, Ca, Sr 1
- Lambert- Beer-Law 2
- writing down complexation reactions 1
- complex formation constants (definition) 2
- Eg and T2g terms: high and low spin octahedral c 3
- calc. of solub. of AgCl in NH3 (from Ks and ß's) 3
- cis and trans forms 3
- n, l, m quantum numbers 2
- energy levels of hydrogen atom (formula) 2
- shape of p- orbitals 2
- d orbital stereoconfiguration 3
- molecular orbital diagram: H2 molecule 3
- - N2 or O2 molecule 3
- bond orders in O2 or O2+ or O2- 3
- Hueckel theory for aromatic compounds 3
- Lewis acids and bases 2
- hard and soft Lewis acids 3
- unpaired electrons and paramagnetism 2
- square of the wave function and probability 3
- understanding the simplest Schroedinger equation 3 l>