Prescribed atoms as having a positive nucleus with electrons that have different energies at different distances from the nucleus

Answer

Niels Bohr

Explanation

in 1915, Niel Bohr proposed a model of the atom which is known as Bohr Model of atoms. Bohr modified the Rutherford Model of atom and some people called this model as Rutherford-Bohr Model. Bohr model was based on quantum mechanics.

The Bohr Model was similar to planetary model. According to Bohr, electrons which are negatively charged are present in an orbit around the positively charged nucleus in a similar manner like planets revolves around the Sun in an orbit. .

main postulates of Bohr's model are as follows

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.