MCQ practice · SSC Chemistry Board questions · Chapter 7: Chemical Reactions
What is the oxidation number of oxygen in NaO₂?
Think it through first, then pick an option.
- a − 2
- b − 1
- c − ½
- d + ½
Answer and explanation
Correct answer: c − ½
In a superoxide O = −½: (+1) + 2x = 0.
Why the other options are wrong
- a − 2: −2 is for ordinary oxides; NaO₂ is a superoxide.
- b − 1: −1 is for peroxides; superoxides are −½.
- d + ½: Oxygen is negative here, −½.
Your account is open, so all 30,000+ MCQs from every chapter are yours. Start practising SSC Chemistry →
Want to keep going?
A free account carries you on to the next questions and opens 30,000+ MCQs from every chapter. Join before launch and Chirkut bundles are 60% off.
The ones you missed, worth one more look