Question

How does quantum theory explain the emission spectra of atoms?

Answer 1

Answer:

B. A single, specific amount of energy is associated with each movement of an electron between energy levels.

Explanation:

As we know by the Bohr's theory that total energy of an electron in a given energy state is given by

$E_n = -13.6 \frac{z^2}{n^2}$

now here if we will find the change in energy of two states then it is given by

$\Delta E = E_2 - E_1$

$\Delta E = 13.6 z^2(\frac{1}{n_1^2} - \frac{1}{n_2^2})$

now when this specific amount of energy is absorbed by the electron then only it will change the state of energy.

so here correct answer will be

B. A single, specific amount of energy is associated with each movement of an electron between energy levels.

Answer 2

The correct answer is B.

Let us think of the classical theory first. In the classical theory, light is a wave that gives energy. This energy gradually helps the electron jump to a higher energy level.
In quantum theory, this is wrong; an electron cannot absorb a small amout of energy because there is not close enough state to jump to with that energy; only very specific amounts of energy lead to a change in orbital levels/ absorbance of energy. Also, each pair of energy levels has a specific energy difference that is needed from an electron so that it can move.
Hence, B is correct; all other sentences describe classical models of light-electron interactions