List I (Spectral Lines of Hydrogen for transitions from) | List II (Wavelength (nm)) | ||
A. | n2 = 3 to n1 = 2 | I. | 410.2 |
B. | n2 = 4 to n1 = 2 | II. | 434.1 |
C. | n2 = 5 to n1 = 2 | III. | 656.3 |
D. | n2 = 6 to n1 = 2 | IV. | 486.1 |
Step 1: Recall the Balmer Series Formula
The Balmer series describes transitions to \( n_1 = 2 \) in the hydrogen atom. The wavelength of emitted light is given by:
$$ \frac{1}{\lambda} = R \left( \frac{1}{n_1^2} - \frac{1}{n_2^2} \right) $$
Where:
\(\lambda\) = Wavelength of emitted light
R = Rydberg constant
n₁ = Lower energy level (\( n_1 = 2 \) for the Balmer series)
n₂ = Higher energy level (\( n_2 > 2 \))
Step 2: Match Wavelengths
Using known values of wavelengths for each transition:
\( n_2 = 3 \rightarrow n_1 = 2 \) : 656.3 nm → (A-III)
\( n_2 = 4 \rightarrow n_1 = 2 \) : 486.1 nm → (B-IV)
\( n_2 = 5 \rightarrow n_1 = 2 \) : 434.1 nm → (C-II)
\( n_2 = 6 \rightarrow n_1 = 2 \) : 410.2 nm → (D-I)
Step 3: Conclusion
The correct matching is:
A-III
B-IV
C-II
D-I
The angular momentum of an electron in a stationary state of \(Li^{2+}\) (\(Z=3\)) is \( \frac{3h}{\pi} \). The radius and energy of that stationary state are respectively.
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A | Robert May | I | Species-Area relationship |
B | Alexander von Humboldt | II | Long term ecosystem experiment using out door plots |
C | Paul Ehrlich | III | Global species diversity at about 7 million |
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B | Proterozoic Era | II | Fish & Amphibia |
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