JEE Main 12 Jan 2019 Morning Question 3

Question: A metal on combustion in excess air forms X. X upon hydrolysis with water yields $ H _2O _2 $ and $ O _2 $ along with another product. The metal is [JEE Main Online Paper Held On 12-Jan-2019 Morning]

Options:

A) Li

B) Rb

C) Mg

D) Na

Show Answer

Answer:

Correct Answer: B

Solution:

  • K, Rb and Cs form super oxides on reaction with excess air. $ Rb+O _2\to RbO _2 $ $ 2RbO _2+2H _2O\to 2RbOH+H _2O _2+O _2\uparrow $