“Bohr’s Model” MCQ with Answer Explanation.

Here below some basic MCQ’s about “Bohr’s Model” with answer which is explained in details. Let’s check one by one which is given below.

1. What does the Bohr model primarily describe?

A) Chemical bonding
B) Atomic structure
C) Nuclear fission
D) Electron clouds

Answer: B) Atomic structure

Explanation: The Bohr model is a theoretical framework that describes the structure of atoms, particularly how electrons are arranged around the nucleus.

2. According to Bohr’s model, which of the following statements is true about electron orbits?

A) Electrons can exist anywhere around the nucleus.
B) Electrons occupy fixed orbits with specific energy levels.
C) Electrons are found only in the nucleus.
D) Electrons emit energy in all positions.

Answer: B) Electrons occupy fixed orbits with specific energy levels.

Explanation: Bohr proposed that electrons move in defined circular paths (orbits) around the nucleus, each associated with a specific energy level.

3. What is the primary postulate of Bohr’s model regarding electron energy?

A) Energy is continuous.
B) Energy levels are quantized.
C) Energy levels can be freely adjusted.
D) Energy is released only when electrons collide.

Answer: B) Energy levels are quantized.

Explanation: Bohr’s model introduced the concept that electrons can only occupy certain discrete energy levels, not the values in between.

4. Which phenomenon did Bohr’s model successfully explain?

A) Chemical reactions
B) Emission spectra of hydrogen
C) Nuclear decay
D) Isotope behavior

Answer: B) Emission spectra of hydrogen

Explanation: Bohr’s model effectively explained the hydrogen emission spectrum by showing that electrons transition between fixed orbits, emitting or absorbing energy in the form of light.

5. In the Bohr model, what happens when an electron moves to a higher energy level?

A) It loses energy.
B) It absorbs energy.
C) It remains stationary.
D) It emits light.

Answer: B) It absorbs energy.

Explanation: An electron moves to a higher energy level by absorbing a specific amount of energy, which allows it to transition to a more excited state.

6. What is the limitation of the Bohr model?

A) It cannot explain the hydrogen spectrum.
B) It only applies to multi-electron atoms.
C) It does not account for electron-electron interactions.
D) It assumes electrons are stationary.

Answer: C) It does not account for electron-electron interactions.

Explanation: The Bohr model primarily addresses hydrogen and cannot accurately describe more complex atoms with multiple electrons interacting.

7. According to Bohr’s model, what is the relationship between the radius of an electron orbit and its energy?

A) Larger radius means lower energy.
B) Larger radius means higher energy.
C) Radius is independent of energy.
D) All orbits have the same radius.

Answer: A) Larger radius means lower energy.

Explanation: In Bohr’s model, the electron in an orbit further from the nucleus has more energy than in a closer orbit, with larger radii correlating to lower overall potential energy.

8. What does the term “quantum leap” refer to in the context of Bohr’s model?

A) Transition between any two orbits.
B) Instantaneous transition between energy levels.
C) Continuous movement of electrons.
D) Emission of multiple photons at once.

Answer: B) Instantaneous transition between energy levels.

Explanation: A quantum leap refers to the abrupt transition of an electron from one energy level to another without occupying the space in between.

9. Which of the following best describes the energy of an electron in a Bohr model orbit?

A) It is always increasing.
B) It is constant and equal for all orbits.
C) It is negative and becomes less negative as it moves farther from the nucleus.
D) It is positive and becomes more positive with distance.

Answer: C) It is negative and becomes less negative as it moves farther from the nucleus.

Explanation: The energy of the electron is considered negative due to its bound state, and as it moves to higher orbits, the energy increases (becomes less negative).

10. Which of the following best characterizes the allowed orbits in Bohr’s model?

A) They are defined by any integer.
B) They correspond to whole number multiples of a fundamental radius.
C) They are based on continuous values.
D) They can vary depending on the temperature.

Answer: B) They correspond to whole number multiples of a fundamental radius.

Explanation: The allowed orbits in Bohr’s model are quantized, represented by specific integers (n = 1, 2, 3, …), which correspond to defined radii.