Intellectual Olympiad in Chemistry - 2026 ongoing
1000 ₸
Subject: Chemistry Level: V (I is easiest, XII is hardest)
Category: educator
Question language: Русский
Questions: 15
Example question: Какова степень окисления хрома в дихромат-ионе Cr₂O₇²⁻? +3, +4, +6, +7