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JEE Main201912 Jan 2019Morning ShiftChemistrys Block ElementsActual

A metal on combustion in excess air forms X . X upon hydrolysis with water yields H 2 O 2 and O 2 along with another product. The metal is:

Options

  1. AN a
  2. BM g
  3. CL i
  4. DR b

Correct answer

D. R b

Step-by-step solution

K , R b and C s form super oxides on reaction with excess air R b + O 2 → R b O 2 (excess) 2 R b O 2 + 2 H 2 O → 2 R b O H + H 2 O 2 + O 2 ↑

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