Question

Which of these electron transitions correspond to absorption of energy and which to emission?
(a) n = 2 to n = 4
(b) n = 3 to n = 1
(c) n = 5 to n = 2
(d) n = 3 to n = 4

Answer 1

Answer:

For a: The energy will be absorbed.

For b: The energy will be released.

For c: The energy will be released.

For d: The energy will be absorbed.

Explanation:

There are two ways in which electrons can transition between energy levels:

• Absorption spectra: This type of spectra is seen when an electron jumps from lower energy level to higher energy level. In this process, energy is absorbed.
• Emission spectra: This type of spectra is seen when an electron jumps from higher energy level to lower energy level. In this process, energy is released in the form of photons.

Equation used to calculate the energy for a transition:

$E=-2.178\times 10^{-18}J\left(\frac{1}{n_i^2}-\frac{1}{n_f^2} \right )$

For the given options:

• For a:  n = 2 to n = 4

As, the electron is getting jumped from lower energy level (n = 2) to higher energy level (n = 4), the energy will be absorbed.

• For b:  n = 3 to n = 1

As, the electron is getting jumped from higher energy level (n = 3) to lower energy level (n = 1), the energy will be released.

• For c:  n = 5 to n = 2

As, the electron is getting jumped from higher energy level (n = 5) to lower energy level (n = 2), the energy will be released.

• For d:  n = 3 to n = 4

As, the electron is getting jumped from lower energy level (n = 3) to higher energy level (n = 4), the energy will be absorbed.