Match List I with List II
| LIST I | LIST II | ||
|---|---|---|---|
| A. | Lyman series | I. | near infrared |
| B. | Balmer series | II. | Ultra violet |
| C. | Paschen series | III. | Visible |
| D. | Brackett series | IV. | Mid infra-red |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → A-II, B-III, C-I, D-IV
The lines of hydrogen are grouped into series by the lower level \( n \) to which the electron falls. The larger the energy gap, the shorter the wavelength, so as \( n \) increases the series move from the ultraviolet to the infrared.
(A) Lyman series — this matches (II) Ultra violet. The electron falls to \( n = 1 \), the largest energy gaps, so the lines are in the ultraviolet.
(B) Balmer series — this matches (III) Visible. The electron falls to \( n = 2 \), and these are the lines the eye sees.
(C) Paschen series — this matches (I) near infrared. The electron falls to \( n = 3 \), and the lines lie just beyond the red end of the spectrum.
(D) Brackett series — this matches (IV) Mid infra-red. The electron falls to \( n = 4 \); the energy gaps are smaller still, so the wavelengths are longer than those of the Paschen series.
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).”
Spectral Series – “… The Lyman series is in the ultraviolet, and the Paschen and Brackett series are in the infrared region.”