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JEE Main202315 Apr 2023Morning ShiftChemistrys Block ElementsActual

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R : Assertion (A) : BeCl 2 and MgCl 2 produce characteristic flame Reason (R) : The excitation energy is high in BeCl 2 and MgCl 2 In the light of the above statements, choose the correct answer from the options given below:

Options

  1. AA is true but R is false
  2. BBoth A and R are true but R is NOT the correct explanation of A
  3. CBoth ( A and R are true and R is the correct explanation of A
  4. DA is false but R is true

Correct answer

D. A is false but R is true

Step-by-step solution

In Be   and   Mg , the electrons are strongly bound. The energy required to excite these electrons is very high. Therefore, when the electron reverts back to its original position, the energy released does not fall in the visible region. Hence, no colour in the flame is seen.

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