Match List I with List II
| LIST I | LIST II | ||
|---|---|---|---|
| A. | Lyman Series | I. | Near infrared region |
| B. | Balmer Series | II. | Far infrared region |
| C. | Paschen Series | III. | Ultraviolet region |
| D. | Pfund Series | IV. | Visible region |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → A-III, B-IV, C-I, D-II
The lines of hydrogen fall into series according to the lower level n to which the electron drops. The larger the energy gap, the shorter the wavelength, so the series move from ultraviolet to far infrared as n increases.
(A) Lyman Series — this matches (III) Ultraviolet region. The electron falls to \( n = 1 \), the largest energy gaps, so the lines are in the ultraviolet.
(B) Balmer Series — this matches (IV) Visible region. The electron falls to \( n = 2 \); these are the lines the eye sees (red, blue-green and violet ones).
(C) Paschen Series — this matches (I) Near infrared region. The electron falls to \( n = 3 \), and these lines lie just beyond the red end of the spectrum.
(D) Pfund Series — this matches (II) Far infrared region. The electron falls to \( n = 5 \), the smallest energy gaps of the four, so these lines have the longest wavelengths.
Note: This question is from the pre-rationalised NCERT book (2022-23). The topic was removed from the latest NCERT book (2026-27), but it is still in the CUET 2026 syllabus, so do not skip it.
NCERT (Pre-rationalised edition, 2022-23):
Spectral Series – “… In 1885, the first such series was observed by a Swedish school teacher Johann Jakob Balmer (1825–1898) in the visible region of the hydrogen spectrum. This series is called Balmer series (Fig. 12.6). … The Lyman series is in the ultraviolet, and the Paschen and Brackett series are in the infrared region.”