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Find the largest and shorted wavelengths...

Find the largest and shorted wavelengths in the Lyman
series for hydrogen. In what region of the electromagnetic spectrum does each
series lie?

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To find the largest and shortest wavelengths in the Lyman series for hydrogen, we will use the Rydberg formula for hydrogen spectral lines. The formula is given by: \[ \frac{1}{\lambda} = RZ^2 \left( \frac{1}{n_1^2} - \frac{1}{n_2^2} \right) \] where: - \(\lambda\) is the wavelength, - \(R\) is the Rydberg constant (\(1.097 \times 10^7 \, \text{m}^{-1}\)), - \(Z\) is the atomic number (for hydrogen, \(Z = 1\)), - \(n_1\) is the principal quantum number of the lower energy level, - \(n_2\) is the principal quantum number of the higher energy level. ### Step 1: Finding the Largest Wavelength For the Lyman series, the lower energy level is \(n_1 = 1\) and the higher energy level \(n_2\) can take values starting from 2 to infinity. To find the largest wavelength, we take \(n_2 = 2\): \[ \frac{1}{\lambda_{\text{max}}} = R \cdot 1^2 \left( \frac{1}{1^2} - \frac{1}{2^2} \right) \] Calculating this gives: \[ \frac{1}{\lambda_{\text{max}}} = 1.097 \times 10^7 \left( 1 - \frac{1}{4} \right) = 1.097 \times 10^7 \left( \frac{3}{4} \right) \] \[ \frac{1}{\lambda_{\text{max}}} = 1.097 \times 10^7 \times \frac{3}{4} = 8.2275 \times 10^6 \, \text{m}^{-1} \] Now, taking the reciprocal to find \(\lambda_{\text{max}}\): \[ \lambda_{\text{max}} = \frac{1}{8.2275 \times 10^6} \approx 1.215 \times 10^{-7} \, \text{m} = 1215 \, \text{Å} \] ### Step 2: Finding the Shortest Wavelength For the shortest wavelength, we take \(n_2\) approaching infinity: \[ \frac{1}{\lambda_{\text{min}}} = R \cdot 1^2 \left( \frac{1}{1^2} - \frac{1}{\infty^2} \right) = R \cdot 1^2 \left( 1 - 0 \right) \] Thus: \[ \frac{1}{\lambda_{\text{min}}} = R = 1.097 \times 10^7 \, \text{m}^{-1} \] Taking the reciprocal gives: \[ \lambda_{\text{min}} = \frac{1}{1.097 \times 10^7} \approx 9.128 \times 10^{-8} \, \text{m} = 91.28 \, \text{Å} \] ### Step 3: Identifying the Region of the Electromagnetic Spectrum The Lyman series lies in the ultraviolet region of the electromagnetic spectrum. ### Summary of Results - Largest wavelength (\(\lambda_{\text{max}}\)): 1215 Å - Shortest wavelength (\(\lambda_{\text{min}}\)): 91.28 Å - Region of the electromagnetic spectrum: Ultraviolet region

To find the largest and shortest wavelengths in the Lyman series for hydrogen, we will use the Rydberg formula for hydrogen spectral lines. The formula is given by: \[ \frac{1}{\lambda} = RZ^2 \left( \frac{1}{n_1^2} - \frac{1}{n_2^2} \right) \] where: - \(\lambda\) is the wavelength, ...
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