What is the oxidation number of chromium in K2Cr2O7?
Answer and explanation
Correct answer: A. +6
- Step 1: Potassium is +1 (two atoms give +2) and oxygen is -2 (seven atoms give -14). Step 2. Two chromium atoms must total +12, so each is +6. Answer: +6. Why not the others: An endothermic reaction has a positive standard enthalpy change; an isobaric reaction maintains constant pressure; and an adiabatic process involves zero thermal heat transfer.
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