Answer:
quantum mechanical theory; it says that quantized energy makes the location of electrons uncertain
Explanation:
According to the wave particle duality theory, particles have wavelike properties and vice-versa.
We can not measure both the velocity and position of a particle simultaneously.
The quantum mechanical model now introduces the idea that the electron is not localized at a particular position within the atom. Hence, the exact location of the electron within the atom is uncertain. This is quite in line with the Heisenberg uncertainty principle