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
A hydrogen atom consists of an electron revolving in a circular orbit of radius r with certain velocity v around a proton located at the nucleus of the atom. The electrostatic force of attraction between the revolving electron and the proton provides the requisite centripetal force to keep it in the orbit. According to Bohr’s model, an electron can revolve only in certain stable orbits. The angular momentum of the electron in these orbits is some integral multiple of \(\frac{h}{2π}\), where h is the Planck’s constant.
Ion | Q4+ | Xb+ | Yc+ | Zd+ |
---|---|---|---|---|
Radius (pm) | 53 | 66 | 40 | 100 |
Q4+, Xb+, Yc+, Zd+ are respectively
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B. \(\textit{Lactobacillus}\)
C. \(\textit{Trichoderma polysporum}\)
D. \(\textit{Saccharomyces cerevisiae}\)
E. \(\textit{Propionibacterium sharmanii}\)
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