International Chemistry Olympiad (IChO)

An International Information Centre of the International Chemistry Olympiads is located in Bratislava, Slovakia. It collates all the information and documentation of the IChOs from the beginning of the Olympiad to the present. 

 Official Webpage

https://www.iuventa.sk/en/Subpages/ICHO/ICHO.alej

Past IChO tasks
https://www.iuventa.sk/en/Subpages/ICHO/Past-Competition-Problems.alej

 Past Preparatory problems
https://www.iuventa.sk/en/Subpages/ICHO/Past-Preparatory-Problems.alej

National Papers from other countries

U.S. National Chemistry Olympiad

German National Olympiad

U.K. National Chemistry Olympiad

Austrian Chemistry Olympiad

Belarus Chemistry Olympiad

Polish Chemistry Olympiad

Ukrainian Chemistry Olympiad