Electrons were embedded in a uniform sphere of positive charge

Atom is composed of empty space mostly with electrons orbiting in a set, predictable paths around fixed, positively charged nucleus.

Electrons revolve around the nucleus in a fixed circular path at very high speed. These fixed circular paths were termed as “orbits.”

Electron will have more energy if it is located away from the nucleus whereas the electrons will have less energy if it located near the nucleus.

Every circular orbit will have a certain amount of fixed energy and these circular orbits were termed orbital shells.

The different energy levels are denoted by integers such as n=1 or n=2 or n=3 and so on. These are called as quantum numbers.

Electrons move from lower to higher energy level by acquiring the required energy and electron loses energy it moves from higher to lower energy level.

It contradicts Heisenberg Uncertainty Principle.

Unable to explain how to determine the spectra of larger atoms.

The path of an electron around the nucleus, in general, is an ellipse with the nucleus at one of its foci.

The velocity of the electron moving in an elliptical orbit varies at different parts of the orbit. This causes the relativistic variation in the mass of the moving electron.

The varying distance of the electron from the nucleus (r).

The varying angular position of the electron with respect to the nucleus i.e the azimuthal angle φ

We cannot measure the position (x) and the momentum (p) of a particle with absolute precision.

Uncertainties in the products of “conjugate pairs” (momentum/position) and (energy/time) were defined by Heisenberg as having a minimum value corresponding to Planck’s constant divided by 4π.

Where Δ refers to the uncertainty in that variable and h is Planck's constant.