Question

Match LIST-I with LIST-II
LIST-I
(A) Lyman Series
(B) Balmer Series
(C) Paschen Series
(D) Pfund Series
LIST-II
(I) Microwave Range
(II) Ultraviolet Range
(III) Visible Range
(IV) Infrared Range

• A. A - I, B - II, C - III, D - IV
• B. A - II, B - III, C - I, D - IV
• C. A - I, B - II, C - IV, D - III
• D. A - II, B - III, C - IV, D - I

Hint:

Remember the order of the hydrogen spectral series by the final energy level \(n_f\): 1. Lyman (\(n_f=1\)) -> Ultraviolet 2. Balmer (\(n_f=2\)) -> Visible 3. Paschen (\(n_f=3\)) -> Infrared 4. Brackett (\(n_f=4\)) -> Infrared 5. Pfund (\(n_f=5\)) -> Infrared

Answer 1

The Correct Option is D

Step 1: Analyze Lyman Series (A)
The Lyman series corresponds to electron transitions from higher energy levels (\(n > 1\)) down to the ground state (\(n=1\)). These transitions involve large energy changes, resulting in photons with high energy and short wavelengths, which fall in the Ultraviolet (II) range. So, A matches with (II).

Step 2: Analyze Balmer Series (B)
The Balmer series corresponds to transitions from \(n > 2\) to the \(n=2\) level. The energy changes are smaller than Lyman, and the first few lines of this series fall within the Visible (III) part of the electromagnetic spectrum. So, B matches with (III).

Step 3: Analyze Paschen Series (C)
The Paschen series corresponds to transitions from \(n > 3\) to the \(n=3\) level. These transitions have even smaller energies and longer wavelengths, falling in the Infrared (IV) range. So, C matches with (IV).

Step 4: Analyze Pfund Series (D)
The Pfund series involves transitions from \(n > 5\) to the \(n=5\) level. These are very low energy transitions with long wavelengths, also in the Infrared (IV) range (specifically, far-infrared). Given the options, matching it to Microwave (I) might be an intended simplification in the question, but Infrared is more accurate. Assuming the intended match is based on the available distinct options, and acknowledging that Paschen, Brackett, and Pfund series are all in the Infrared range, there's ambiguity. However, following the pattern A-II, B-III, C-IV, D-I is presented in option (D).