Question

Hydrogen atoms are excited from ground state of the principal quantum number 4. Then the number of spectral lines observed will be.

• A. 3
• B. 6
• C. 5
• D. 2

Answer 1

Answer: (B)

6

Answer 2

Number of spectral lines $N_{E} = \frac{n(n - 1)}{2} = \frac{4(4 - 1)}{2} = 6$.