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Question
Which of the following curves may represent the speed of the electron in a hydrogen atom as a function of trincipal quantum number n?
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Solution
(c)
The speed (v) of electron can be expressed as
`v = (Ze^2)/(2∈_0hn)` ....(1)
Here,
Z = Number of protons in the nucleus
e = Magnitude of charge on electron charge
n = Principal quantum number
h = Planck's constant
It can be observed from equation (1) that the velocity of electron is inversely proportional to the principal quantum number (n).
Therefore, the graph between them must be a rectangular hyperbola.
The correct curve is (c).
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