Quantum number

 A set of number or quantities that can explain the possible state of the system within atom. In hydrogen like atom to state the position, orientation and spin of the electron there have four quantum number. 

Principle quantum numner

Azimuthal quantum number 

Magnetic quantum number 

Spin quantum number.

To describe the states of subatomic particles there need new quantum number. For examples, flavor of quark can describes by another new quantum number.

1. Principle Quantum number describes in which energy state electron placed. If it placed in 4th energy state then principle quantum number would be 4.

Indicates atomic size and Randi,  the distance of electron from nucleus

Indicates the energy of an electron 

It should be positive value equal to 1 or greater than 1

Increased value of quantum number of an atom indicates the absorption of energy

Azitmuthal quantum number indicates the shape of the orbital. It is the total number of angular node of orbital. 

The azimuthal quantum number indicates electrons position either in S,  p,  d or f orbital

It's value depends on principle quantum number. It should be 0 to n - 1

If n is 3, the possible azimuthal quantum number would be 0, 1, 2.

Hence,  the subshell would be S,  p,  d

In third energy state 3d orbital is possible.

But in second energy state 2d orbital is not possible. Because in second energy state azimuthal quantum number is 0, 1. Hence, 2d is not possible.

Magnetic quantum number indicates possible orientation of orbitals and the total number of orbital in a subshell. 

It's value is related to azimuthal quantum number as well as principle quantum number. It is equal to 2l+1.

If azimuthal quantum number is 2, the magnetic quantum number would be -2, -1, 0, +1, +2

In 3rd energy state 3d is possible. In 3d orbital azimuthal quantum number would be 2. Hence,  magnetic quantum number is -2, -1, 0, +1, +2. Here, number 5 orbital exist. Each orbital can contain maximum 2 electron. Hence, total number of electron in 3d orbital is 10.

Spin quantum number of any electron would be +½ and -½.

Bohr atomic model

 Where Rutherford model can not explain the spectra of hydrogen atom, Bohr model can explain the spectra of hydrogen atom.  Moreover,  Bohr model introduces the circular fixed orbit that negativity charged electron revolves surrounding the the nucleus along with fixed orbit.

1. Electron revolves surrounding nucleus along with fixed circular orbit. These orbits are called energy state. Electron can jump from lower energy state to higher energy state and from higher energy state to lower energy state. 

1. Each orbit have specific energy. The orbit far from nucleus have highest energy. Electron to stay highest energy state orbit required highest energy. 

3. Energy state is defined as shel, named as K,  L,  M, N, O, P

4. When electron jump to lower energy state it releases energy, this amount is equal to mvr.

Limitation of Bohr Model

1. Bohr model can not explain the spectra of atom of higher atomic mass.

2. No explanation of sub Shel.

3. It does not comply with Heigenburg uncertainty principle. 

4. It can not explain Zeeman effect, which is scattering of spectra into multiple spectral line( fine structure) with the effect of magnetic field.

5. It can not explain Stark effect that means scattering of spectra into multiple  spectral line ( fine structure) with the effect of electric field.

Basic difference of general theory of relativity from Special theory of relativity

 General theory of relativity is an extended form of special theory of relativity. Gravitational force is incorporated with special theory of relativity and developed general theory of relativity. 

Why black hole is not black?

 Black hole is not quite black rather it radiates energy from its event horizon. The radiation emission from event horizon is called Hawking radiation. For that reason black hole looks bright.

Why sky looks blue?

 Sky looks blue. In sky there have a lot of nanoparticles floating. The light or electromagnetic radiation have 7 different color. Each color is dispersing from the particles floating in sky. But Blue color have highest dispersion. For that reason any spectator see sky as blue.