The competition tasks from the past International Chemistry Olympiads (1968 – 2013) are compiled in the publication:
"THE COMPETITION PROBLEMS FROM THE INTERNATIONAL CHEMISTRY OLYMPIADS" Editor: Anton Sirota, Issued by IChO International Information Centre and IUVENTA, Bratislava, Slovakia" (in three volumes):
More details you can find here.
Next Olympiad
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17 August 2016
Official video of closing ceremony
17 August 2016
Official video of closing ceremony
22 July 2016