De-Broglie Wavelength of Electron in 4th Orbit | JEE Main 2024 PYQ | Structure of Atom
Q. The de-Broglie's wavelength of an electron in the 4th orbit is ________ πa0. ( a0 = Bohr's radius )
Explanation
Step 1: de-Broglie wavelength condition

According to Bohr's quantization condition:

2πrn = nλ

Step 2: Radius of nth orbit

Radius of nth orbit of hydrogen atom is:

rn = n2a0

Step 3: Substitute rn in wavelength equation

λ = 2πrn / n = 2π(n2a0) / n = 2πn a0

Step 4: Put n = 4

λ = 2π × 4 × a0 = 8πa0

Correct Answer = 8

Previous Year Questions – Structure of Atom
The maximum number of orbitals which can be identified with n = 4 and ml = 0 is ______.
The maximum number of orbitals which can be identified with n = 4 and ml = 0 is ______.
The incorrect postulates of the Dalton's atomic theory are: (A) Atoms of different elements differ in mass. (B) Matter consists of divisible atoms. (C) Compounds are formed when atoms of different element combine in a fixed ratio. (D) All the atoms of given element have different properties including mass. (E) Chemical reactions involve reorganisation of atoms.
The value of Rydberg constant (RH) is 2.18 × 10−18 J. The velocity of electron having mass 9.1 × 10−31 kg in Bohr's first orbit of hydrogen atom is ______ × 105 m s−1.
In an atom, total number of electrons having quantum numbers n = 4, ml = 1 and ms = −1/2 is ______.
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