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In Li + + , electron in first Bohr orbit is excited to a level by a radiation of wavelength λ . When the ion gets deexcited to the ground state in all possible ways (including intermediate emissions), a total of six spectral lines are observed. What is the value of λ ? (Given : H = 6.63 × 10 –34 Js; c = 3 × 10 8 ms –1 )

1. 12.3 nm
2. 10.8 nm
3. 9.4 nm
4. 11.4 nm CAREER POINT CAREER POINT , CP Tower, IPIA, Road No.1, Kota (Raj.), : 0744-6630500 | www.ecareerpoint.com Email: info@cpil.in Page # 8 JEE Main Online

Correct answer: 10.8 nm

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