Statement I: The Balmer series corresponds to electronic transitions where the electron falls to the n=2 energy level. The lowest energy transition in the Balmer series is from n=3 to n=2. The wavenumber ($\tilde{\nu}$) for this transition can be calculated using the Rydberg formula:
\[ \tilde{\nu} = R_\text{H} \left( \frac{1}{n_1^2} - \frac{1}{n_2^2} \right) \]
For the lowest energy Balmer transition ($n_1$=2, $n_2$=3):
\[ \tilde{\nu} = R_H \left( \frac{1}{2^2} - \frac{1}{3^2} \right) = R_H \left( \frac{1}{4} - \frac{1}{9} \right) = R_H \left( \frac{9 - 4}{36} \right) = \frac{5}{36} R_H \]
The wavenumber is indeed $\frac{5}{36} R_H$ cm$^{-1}$. Thus, statement I is true.
Statement II: Wien's displacement law states that the wavelength of maximum intensity for blackbody radiation is inversely proportional to its temperature. As the temperature increases, the wavelength of maximum intensity shifts to shorter wavelengths. Thus, statement II is true.
The UV-visible spectrum of [Ni(en)\(_3\)]\(^{2+}\) (en = ethylenediamine) shows absorbance maxima at 11200 cm\(^{-1}\), 18350 cm\(^{-1}\), and 29000 cm\(^{-1}\).
[Given: Atomic number of Ni = 28] The correct match(es) between absorbance maximum and electronic transition is/are
Compound K displayed a strong band at 1680 cm−1 in its IR spectrum. Its 1H-NMR spectral data are as follows:
δ (ppm):
7.30 (d, J = 7.2 Hz, 2H)
6.80 (d, J = 7.2 Hz, 2H)
3.80 (septet, J = 7.0 Hz, 1H)
2.20 (s, 3H)
1.90 (d, J = 7.0 Hz, 6H)
The correct structure of compound K is:
The 1H NMR spectrum of the given iridium complex at room temperature gave a single signal at 2.6 ppm, and its 31P NMR spectrum gave a single signal at 23.0 ppm. When the spectra were recorded at lower temperatures, both these signals split into a complex pattern. The intra-molecular dynamic processes shown by this molecule are:
List I | List II | ||
---|---|---|---|
A | Mesozoic Era | I | Lower invertebrates |
B | Proterozoic Era | II | Fish & Amphibia |
C | Cenozoic Era | III | Birds & Reptiles |
D | Paleozoic Era | IV | Mammals |