IOM 2019, Блиц — Задача 42

OLYMPIAD OF METROPOLISES, Moscow, September 2, 2019 · 2 септември 2019 г.

Условие

A piece of shiny, golden iron mineral was placed in a beaker which contained hot concentrated solution of nitric acid. The violent reaction was accompanied by evolution of a brown gas. The latter was completely removed from the reaction mixture, and formation of a dark orange solution was observed. The post-reaction solution gave a bulky white precipitate with barium chloride. What is the sum of all stoichiometric coefficients of the first reaction written in the ionic form? (Take coefficients as minimal integers).

Решение

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Оригинал в Архива: blitz-en-all-task-final.pdf