Wavenumber for Radiation of 5800 Å Wavelength | JEE Mains PYQ | Structure of Atom
Q. Wavenumber for a radiation having 5800 Å wavelength is x × 10 cm−1. The value of x is ______. (Integer answer)
Explanation
Step 1: Formula for wavenumber

Wavenumber (ν̄) = 1 / λ

Step 2: Convert wavelength into cm

1 Å = 10−8 cm
5800 Å = 5800 × 10−8 cm = 5.8 × 10−5 cm

Step 3: Calculate wavenumber

ν̄ = 1 / (5.8 × 10−5)
ν̄ ≈ 1.724 × 104 cm−1

Step 4: Match with given format

ν̄ = x × 10 cm−1
x = 1724

Correct Answer = 1724

Previous Year Questions – Structure of Atom
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 ______.
For hydrogen atom, energy of an electron in first excited state is −3.4 eV. K.E. of the same electron of hydrogen atom is x eV. Value of x is ______ × 10−1 eV.
Frequency of the de-Broglie wave of electron in Bohr’s first orbit of hydrogen atom is ______ × 10¹³ Hz.
JEE Mains Full Study Material
Wavenumber for Radiation of 5800 Å Wavelength | JEE Mains PYQ | Structure of Atom
Q. Wavenumber for a radiation having 5800 Å wavelength is x × 10 cm−1. The value of x is ______. (Integer answer)
Explanation
Step 1: Formula for wavenumber

Wavenumber (ν̄) = 1 / λ

Step 2: Convert wavelength into cm

1 Å = 10−8 cm
5800 Å = 5800 × 10−8 cm = 5.8 × 10−5 cm

Step 3: Calculate wavenumber

ν̄ = 1 / (5.8 × 10−5)
ν̄ ≈ 1.724 × 104 cm−1

Step 4: Match with given format

ν̄ = x × 10 cm−1
x = 1724

Correct Answer = 1724

Previous Year Questions – Structure of Atom
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 ______.
For hydrogen atom, energy of an electron in first excited state is −3.4 eV. K.E. of the same electron of hydrogen atom is x eV. Value of x is ______ × 10−1 eV.
Frequency of the de-Broglie wave of electron in Bohr's first orbit of hydrogen atom is ______ × 10¹³ Hz.
JEE Mains Full Study Material

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