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ChemistryMediumNumerical2022 · 25 Jun Shift 1

Q54.The longest wavelength of light that can be used for the ionisation of lithium ion $\mathrm{(Li^{2+})}$ is x × 10-8 m. The value of x is (Nearest Integer) (Given : Energy of the electron in the first shell of the hydrogen atom is -2 . 2 × 10-18 J; h = 6 . 63 × 10-34Js and c = 3 × 108 ms-1)

What This Question Tests

This question tests the application of Bohr's model for multi-electron species to calculate ionization energy and then relate it to the wavelength of light using Planck's equation.

Concepts Tested

Bohr's modelIonization energyEnergy of electronWavelength of lightHydrogen spectrum

Formulas Used

E_n = -2.18 x 10^-18 J * Z^2/n^2

E = hc/λ

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