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Karnataka Board PUCPUC Science Class 11

What is the maximum number of emission lines when the excited electron of an H atom in n = 6 drops to the ground state?

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Question

What is the maximum number of emission lines when the excited electron of an H atom in n = 6 drops to the ground state?

Numerical
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Solution

When the excited electron of an H atom in n = 6 drops to the ground state, the following transitions are possible:

Hence, a total number of (5 + 4 + 3 + 2 + 1) 15 lines will be obtained in the emission spectrum.

The number of spectral lines produced when an electron in the nth level drops down to the ground state is given by `("n"("n"-1))/2`

Given, n = 6

Number of spectral lines =` (6(6-1))/2 = 15`

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Chapter 2: Structure of Atom - EXERCISES [Page 70]

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NCERT Chemistry Part 1 and 2 [English] Class 11
Chapter 2 Structure of Atom
EXERCISES | Q 2.15 | Page 70

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