Question

The total number of spectral lines expected to be emitted by atomic hydrozen excited to the 5th energy level:

• A. 4
• B. 5
• C. 10
• D. 20

Answer 1

Answer: (C)

Number of spectral lines emitted by atomic hydrogen atom is given as $=\frac{n(n-1)}{2}=\frac{5(5-1)}{2}$ $=10$