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Atoms — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsAtoms1 Mark
Question
For question two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true, and R is the correct explanation of A.
  2. Both A and R are true, but R is NOT the correct explanation of A.
  3. A is true, but R is false.
  4. A is false and R is also false.
Assertion (A): An electron in hydrogen atom passes from n = 4 to n = 1 level. The maximum number of photons that can be emitted is 4.
Reason (R): Maximum number of photons emitted can only be 4
✓

Answer

  1. A is false and R is also false

Explanation:

The maximum number of photons emitted = 6 corresponding to the transitions 4 → 3 ; 3 → 2, 2 → 1, 4 → 2, 4 → 1 and 3 → 1

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