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Question
In which of the following systems will the wavelength corresponding to n = 2 to n = 1 be minimum?
Options
Hydrogen atom
Deuterium atom
Singly ionized helium
Doubly ionized lithium
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Solution
Doubly ionized lithium
The wavelength corresponding the transition from n2 to n1 is given by
`1/lamda =RZ^2 (1/n_1^2 - 1/n_2^2)`]
Here,
R = Rydberg constant
Z = Atomic number of the ion
From the given formula, it can be observed that the wavelength is inversely proportional to the square of the atomic number.
Therefore, the wavelength corresponding to n = 2 to n = 1 will be minimum in doubly ionized lithium ion because for lithium, Z = 3.
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