Concept:Potassium (K) forms a normal oxide (\( \text{K}_2\text{O} \)), a peroxide (\( \text{K}_2\text{O}_2 \)), and a superoxide (\( \text{KO}_2 \)). The oxygen-to-metal ratio determines which contains "more" oxygen.
Solution:- Normal Oxide (\( \text{K}_2\text{O} \)): 2 Potassium atoms to 1 Oxygen atom. Ratio = 0.5 oxygen per K.
- Peroxide (\( \text{K}_2\text{O}_2 \)): 2 Potassium atoms to 2 Oxygen atoms. Ratio = 1 oxygen per K.
- Superoxide (\( \text{KO}_2 \)): 1 Potassium atom to 2 Oxygen atoms. Ratio = 2 oxygen per K.
- Comparing the ratios, the superoxide molecule contains the highest proportion of oxygen relative to the metal. Potassium naturally favors forming the superoxide when burned in excess air.
Why other options are incorrect:- While peroxides contain more oxygen than normal oxides, superoxides contain even more than peroxides, making it the most correct answer for "more oxygen".
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