Bohr Model of the Hydrogen Atom

IMPORTANT

Bohr Model of the Hydrogen Atom: Overview

This topic covers concepts, such as, Bohr Model, Bohr Postulates of H-atom, Drawbacks of Rutherford Model of Atom & Explanation of Line Spectra in Hydrogen Atom Using Bohr's Model etc.

Important Questions on Bohr Model of the Hydrogen Atom

EASY
IMPORTANT

The energy of the electron, the hydrogen atom, is known to be expressible in the form

E n = 13.6 eV n 2 ( n=1,2,3,.......... )

Use this expression, which of the following statement is/are true?

(i) Electron in the hydrogen atom cannot have energy of 2 eV.

(ii) Spacing between the lines (consecutive energy levels) within the given set of the observed hydrogen spectrum decreases as n increases.

EASY
IMPORTANT

The ground state energy of the hydrogen atom is 13.6 eV . The kinetic and potential energies of electrons in this state are:

EASY
IMPORTANT

Find the ratio of energies of photons produced due to the transition of an electron of a hydrogen atom from its
(i) second permitted energy level to the first level, and
(ii) the highest permitted energy level to the first permitted level.

EASY
IMPORTANT

For a hydrogen atom the value of ionization energy is equal to:

EASY
IMPORTANT

The ground state energy of hydrogen atom is -13.6 eV.

(i) What is the kinetic energy of an electron in the 2nd excited state?

(ii) If the electron jumps to the ground state from the 2nd excited state, calculate the wavelength of the spectral line emitted.

MEDIUM
IMPORTANT

The frequency of radiation emitted when the electron falls from   n=4ton=1 in a hydrogen atom will be (Given ionization energy of   H=2.18× 10 18 Jato m 1 andh=6.625× 10 34 Js )

                                                                                                                                                                                                                               

MEDIUM
IMPORTANT

In hydrogen atom, energy of first excited state is   3.4eV . Find out KE of the same orbit of Hydrogen atom

                                                                                                                                                                                                                               

EASY
IMPORTANT

According to Bohr’s theory the energy required for an electron in the   L i 2+  ion to be emitted from n = 2 state is (given that the ground state ionization energy of hydrogen atom is 13.6 eV)

                                                                                                                                                                                                                               

EASY
IMPORTANT

The Bohr orbit radius for the hydrogen atom (n = 1) is approximately   0.530Å.  The radius for the first excited state (n = 2) orbit is   (inÅ)

EASY
IMPORTANT

The recoil speed of a hydrogen atom after it emits a photon in going from n=5 state to n=1 state is

EASY
IMPORTANT

The Bohr radius of the fifth electron of the phosphorous atom (atomic number=15) acting as a dopant in silicon (relative dielectric constant=12) is

EASY
IMPORTANT

The Bohr radius of the fifth electron of phosphorous atom (atomic number=15) acting as a dopant in silicon (relative dielectric constant=12) is ___________ Å

HARD
IMPORTANT

The Bohr radius of the fifth electron of phosphorous atom (atomic number =15) acting as a dopant in silicon (relative dielectric constant =12) is ___________ A.

EASY
IMPORTANT

Orbit velocity of hydrogen atomv varies with number of orbit n as

EASY
IMPORTANT

Fine structure constantα has value

EASY
IMPORTANT

According to the rutherford's model, entire positive charge is concentrated in the centre of the atom.

EASY
IMPORTANT

In Bohr's model of hydrogen atom, linear momentum (pn) of the electron depends on the principal quantum number (n) as:

HARD
IMPORTANT

Suppose the potential energy between the electron and proton at a distance r is given by -ke23r3. Application of Bohr's theory of hydrogen atom, in this case, shows that energy in the nth orbit is proportional to :

EASY
IMPORTANT

Bohr's theory can be applied to Li+ ion.

HARD
IMPORTANT

A photon falls through a height of 1 km through the earth's gravitational field. To calculate the change in its frequency, take its mass to be hvc2. The fractional change in frequency v is close to