O-LevelChemistryStoichiometry5070/11 · Oct/Nov 2022 · Q141 Mark

The atomic number of ruthenium is 44. One of the oxides of ruthenium is a black solid, X. 5.79 g of X contains 1.39 g of oxygen. What is the empirical formula of X?

ARu2O

BRuO

CRuO2

DRuO4

✓ Correct answer

C: RuO2

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, Oct/Nov 2022 Paper 1 Variant 1, question 14.

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