Question

In which transition, one quantum of energy is emitted?
\[
  A.{\text{ }}n = 4 \to n = 2 \\
  B.{\text{ }}n = 3 \to n = 2 \\
  C.{\text{ }}n = 4 \to n = 1 \\
  D.{\text{ All of them}} \\
 \]

Answer 1

Hint- In order to deal with this question we will use the basic concept from Bohr’s atomic model. Whenever an electron jumps from higher energy to lower energy the energy is released. We will check for all the options where the transition is from higher to lower energy state in order to conclude the answer.

Complete answer:
As we know that whenever an electron jumps from higher energy level to lower energy level, a quantum of energy is emitted.
So here we will check the each given options
Considering option A
In this transition, an electron jumps from fourth energy level to second energy level, so according to the above concept electron jumps from higher energy level to lower energy level, a quantum of energy is emitted.
Taking option B
In this transition, the electron jumps from third energy level to first energy level, so according to the concept electron jumps from higher energy level to lower energy level, a quantum of energy is emitted.
Taking option C
In this transition, the electron jumps from fourth energy level to first energy level, so according to the concept electron jumps from higher energy level to lower energy level, a quantum of energy is emitted.
Therefore, above all the transitions energy is transmitted.
Hence the correct answer is option D.

Note- The concept of energy level comes from the Bohr’s atomic model. According to this model Electrons have a set number of orbital, ring-like paths around the nucleus; they can travel in so-called stationary states. If the electron stays in one orbital, the energy of the electron remains constant. The first orbital is n=1, the second orbital n=2 and so on. (These values of n are called quantum numbers.) Electrons can only move from one orbital to another allowed orbital at one time. If an electron drops down from n=2 to n=1 energy is emitted, and if the electron moves up from n=1 to n=2 energy is absorbed. The amount of energy that is either absorbed or emitted is called quanta.