What is the main concept of Bohr’s Atomic Model?
a) Electrons revolve in fixed orbits around the nucleus
b) Electrons are scattered randomly in the atom
c) The atom has no nucleus
d) Electrons orbit randomly around the nucleus
In Bohr’s model, what does the electron’s energy depend on?
a) The distance from the nucleus
b) The electron’s mass
c) The number of protons
d) The type of atom
According to Bohr’s model, what happens when an electron absorbs energy?
a) It moves to a lower energy orbit
b) It moves to a higher energy orbit
c) It gets ejected from the atom
d) It becomes part of the nucleus
What is the relationship between the frequency of emitted radiation and the energy difference between two orbits in Bohr’s model?
a) They are inversely proportional
b) They are directly proportional
c) They are unrelated
d) The frequency is always zero
What is the angular momentum of an electron in Bohr’s model?
a) A continuous variable
b) Quantized in integer multiples of h/2π
c) Equal to the total energy of the electron
d) Zero
In Bohr’s model, how are the energy levels of an atom represented?
a) As concentric rings
b) As a cloud
c) As a series of points
d) As a single line
What happens when an electron falls from a higher orbit to a lower orbit in Bohr’s model?
a) It emits energy in the form of radiation
b) It absorbs energy
c) It remains unchanged
d) It becomes unstable
Which element was the Bohr model primarily developed to explain?
a) Oxygen
b) Hydrogen
c) Carbon
d) Helium
What is the energy of an electron in Bohr’s model given by?
a) E = mc²
b) E = -13.6/n²
c) E = hf
d) E = mv²
In Bohr’s model, what is the principal quantum number (n) associated with?
a) The size and energy of an electron’s orbit
b) The number of protons in the nucleus
c) The number of electrons in the atom
d) The speed of the electron
How did Bohr explain the discrete spectral lines observed in the hydrogen atom’s spectrum?
a) Electrons absorb energy from outside sources
b) Electrons move in orbits of fixed radii
c) Electrons jump randomly between energy levels
d) Electrons are stationary in the atom
What is the formula for the energy of an electron in a particular orbit in Bohr’s model?
a) E = h/2π
b) E = -13.6 Z²/n²
c) E = m v²
d) E = hc/λ
What does the letter “n” represent in Bohr’s atomic model?
a) The number of protons in the nucleus
b) The principal quantum number
c) The number of neutrons in the nucleus
d) The electron’s spin number
What is the primary limitation of Bohr’s atomic model?
a) It only explains hydrogen-like atoms
b) It does not account for the stability of atoms
c) It predicts the wrong energy levels
d) It explains electron behavior inaccurately
In Bohr’s model, what is the energy of an electron in the lowest orbit (n = 1)?
a) 0
b) -13.6 eV
c) -1.6 eV
d) +13.6 eV
What causes the line spectra in the hydrogen atom, according to Bohr’s model?
a) Electrons are emitted from the atom
b) Electrons move from one orbit to another
c) Electrons stay in one orbit
d) Protons and neutrons combine to form energy
According to Bohr, why do electrons not spiral into the nucleus?
a) They are stopped by nuclear forces
b) Their angular momentum is quantized
c) Electrons have no charge
d) The nucleus repels electrons
What did Bohr use to explain the stability of electron orbits in his model?
a) Electrons are stationary at fixed distances
b) Electrons emit radiation continuously
c) Electrons are always in motion
d) Electrons are attracted to the nucleus
What happens when an electron in Bohr’s model absorbs energy?
a) It falls to a lower energy level
b) It moves to a higher energy level
c) It stays in its current orbit
d) It becomes free from the atom
What does Bohr’s model assume about electron orbits?
a) They are elliptical
b) They are circular
c) They are three-dimensional
d) They are irregular
In Bohr’s model, how is the emission of radiation explained?
a) By the transition of electrons between energy levels
b) By the movement of protons in the nucleus
c) By the creation of new particles
d) By the breaking of atomic bonds
What is the Bohr model primarily used to explain?
a) Chemical bonding
b) The behavior of electrons in atoms
c) The formation of molecules
d) The color of light emitted by atoms
What principle did Bohr use to derive his model?
a) The uncertainty principle
b) The principle of least action
c) The quantization of energy levels
d) The theory of relativity
In Bohr’s model, what happens to the radius of an electron’s orbit as the energy level increases?
a) The radius decreases
b) The radius remains the same
c) The radius increases
d) The radius becomes zero
Which of the following was a key feature of Bohr’s atomic model?
a) Electrons follow elliptical orbits
b) Electrons are found in fixed orbits with quantized energy levels
c) Electrons are found in any position within the atom
d) Electrons emit energy continuously
What did Bohr’s model replace in the understanding of atomic structure?
a) The Rutherford model
b) The Thomson model
c) The Dalton model
d) The Heisenberg model
