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AP EAMCET202119 Aug 2021Morning ShiftChemistrys Block ElementsActual

Assertion (A): K , Rb and Cs form superoxides Reason (R): The stability of superoxides increases form K to Cs due to decrease in lattice energy.

Options

  1. ABoth A and R are true and R is a correct explanation for A
  2. BBoth A and R are true but R is not a correct explanation for A
  3. CA is true, R is false
  4. DA is false, R is true

Correct answer

C. A is true, R is false

Step-by-step solution

K ,   Rb ,   Cs form superoxides when they are burnt in the air. As we down the group then the size of atom from K to Cs increases so that the lattice energy decreases hence the stability of superoxide also decreases.

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