The balanced half-reaction: Cr²⁺⁺(aq) → Cr⁴⁺(aq) + 2e⁻.
Chromium(II) cations two electrons and became chromium(IV) cations.
<span>Oxidation
reaction is increasing of oxidation number of element, because element or
ion lost electrons in chemical reaction.
</span><span>Reduction is lowering
oxidation number because element or ions gain electrons.</span>
Answer:
40.3 for the unit that represents the minimum amount of magnesium oxide I beilieve.
Explanation:
Magnesium atoms are heavier than oxygen atoms, so we expect more than 50% of magnesium in the weight composition. Taking just one atom of Mg and one atom of O you will get a mass of 16.0 + 24.3 = 40.3.
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