Theoretical part of the IChO

General information

The IChO consists of the experimental and the theoretical parts.

The competition starts with the experimental part and after one day break it continues with a theoretical part that lasts maximum 5 hours. What concerns theoretical tasks there were not so many problems with them in the first years of the competition. Then, however, there were long discussions in the jury before it was achieved that the texts of theoretical problems were acceptable and prepared for their translation. Moreover, the answer sheets were introduced as a novelty.

The organizer is responsible for the preparation of competition tasks by competent experts/authors, who constitute the Scientific Committee (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.

Before the competition starts, the competition tasks are translated by the mentors into mother tongue or language understandable for the competitors.

It was obvious that the mentors required more time for these activities. Since the preparation of the theoretical part for the competition required more time than the experimental part, it was decided by the international jury that the practical part of the competition would be the first followed after one day break by the theoretical part. This model was introduced definitely in the year 1991.

Starting with the year 1976 a maximum of 60 points is allocated to the theoretical tasks and 40 points to the practical tasks, making a total of 100 points.

The competition tasks are corrected independently by the authors and by the mentors. Consequential marking should be used so that students are not punished twice for the same error. Both corrections are then compared and discussed in order to reach the final score for each participant.

The International Jury discusses the results and decides on the final scores.

Some more details about the theoretical part of the IChO are given in the appendix:

Compiled and edited by A. Sirota (IChO Intern. Information Centre)

Contact us

Dr. Anton Sirota|Director of the IChO IIC
NIVaM – National Institute for Education and Youth
Hálova 6, 851 01 Bratislava, Slovakia
E-mail:|Phone: +421 907 473 367

Dr. Martin Putala|Department of Organic Chemistry
Faculty of Natural Sciences
Comenius University, Bratislava, Ilkovičova 6, Slovakia
E-mail:|Phone: +421 918 669 092