JEE Mains · Chemistry · STD 11 - 2. structure of atom
What is the ratio of wave number of first line (lowest energy line) of Balmer series of H atomic spectrum to first line of its Brackett series?
- A \(5:1\)
- B \(5:0.81\)
- C \(5:1.75\)
- D \(5:27\)
Answer & Solution
Correct Answer
(B) \(5:0.81\)
Step-by-step Solution
Detailed explanation
The wave number \(\bar{\nu}\) of a spectral line in the hydrogen emission spectrum is given by the Rydberg formula: \(\bar{\nu} = R_H \left( \dfrac{1}{n_1^2} - \dfrac{1}{n_2^2} \right)\) For the first line (lowest energy) of the Balmer series, the transition is from \(n_2 = 3\)…
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