The International Chemistry Olympiad (IChO) is an annual academic competition for high school students. It is one of the International Science Olympiad

International Science Olympiad

The International Science Olympiads are a group of worldwide annual competitions in various areas of science. The competitions are designed for the 4-6 best high school students from each participating country selected through internal National Science Olympiads, with the exception of the IOL,...

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The first IChO was held in Prague

Prague

Prague is the capital and largest city of the Czech Republic. Situated in the north-west of the country on the Vltava river, the city is home to about 1.3 million people, while its metropolitan area is estimated to have a population of over 2.3 million...

, Czechoslovakia

Czechoslovakia

Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...

, in 1968. The event has been held every year since then, with the exception of 1971. The delegations that attended the first events were mostly countries of the former Eastern bloc

Eastern bloc

The term Eastern Bloc or Communist Bloc refers to the former communist states of Eastern and Central Europe, generally the Soviet Union and the countries of the Warsaw Pact...

 and it was not until 1980, the 12th annual International Chemistry Olympiad, that the event was held outside of the bloc in Austria

Austria

Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...

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Each delegation consists of up to four students and two mentors (one of them is designated as the head of the delegation or "head mentor").