A metal on combustion in excess air forms X. X upon hydrolysis with water yields \(\mathrm{H_2O_2}\) and \(\mathrm{O_2}\) along with another product. The metal is :
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- Rb
- Mg
- Na
- Li
The Correct Option is A
Solution and Explanation
Hydrolysis of the superoxide: \(\mathrm{2RbO_2 + 2H_2O \rightarrow 2RbOH + H_2O_2 + O_2}\), giving H2O2 and O2 together with another product (RbOH).
For comparison, \(\mathrm{Na_2O_2 + 2H_2O \rightarrow 2NaOH + H_2O_2}\) gives no O2.
Answer: (1) Rb
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