Question

How many electrons can the fourth energy level hold according to Neil Bohr?

Answer 1

Hint: To answer this question we should know Bohr's postulates and assumption. Bohr modify Rutherford's model of atom and explained certain postulates of Bohr's model of an atom in 1915.

Complete step by step answer:
Neil Bohr was a Danish physicist who set a foundation in understanding the structure of atoms and other molecular structures by applying certain quantum concepts. According to Neil Bohr's model of the atom, the electrons revolve around the nucleus in its own orbital just like planets revolving around the sun. Different energy levels are associated with different orbits.
 Certain observations from Neil Bohr postulates as follows:
- Each electron in an atom possesses different energy depending upon which orbital the electron belongs as each orbital possesses a different energy level.
- Electrons fill the principal energy level starting n = 1 to n = 7.
- Each energy level can accommodate only a certain number of electrons.
 The maximum number of electron in energy level = $2n^2$
Where. n = the energy level
According to our question we should find the number of electrons in fourth orbital:
$2n^2$
n = 4
2 $\times$ 4 $\times$ 4
32
Thus, the number of electrons in the fourth energy level is 32 electrons.

Note: The maximum number of electron in energy level = $2n^2$
-Bohr explained and gave lead to many discoveries but there are certain limitations of Bohr's model of an atom. The limitations of Bohr's model of an atom are it failed to explain Zeeman effect, stark effect and spectra obtained from large atoms. Most importantly, it violated the Heisenberg uncertainty principle.