Atomic Structure

Question 1.3. Which quantum number is also called sub-shell quantum number?

Answer.

Azimuthal quantum number is also called subshell quantum number as it describes the shape of an orbital or sub-shell. It is denoted by " ℓ". Its numerical values are 0,1,2,3...n-1.

For s - subshell or orbital ℓ = 0

For p - subshell or orbital ℓ = 1

For d - subshell or orbital ℓ = 2

For f - subshell or orbital ℓ = 3

Question 3.4 What is the difference between an orbit and orbital?

Answer.

Orbit

Orbit may be defined as

"The circular path in which electron revolves around the nucleus of an atom".

It is also represented by K, L, M, N,...

It has two dimensional circular planer shape.

It is used to calculate the radius of atom and energy of electron in Bohr atomic theory.

An orbit can accommodate maximum 2n2 electrons.

Orbital

Orbital may be defined as

The space around the nucleus of an atom in which chances of finding the electron are maximum (95 %), is called orbital.

It is also represented by s, p, d or f.

It has three dimensional eleptical shape.

An orbital can accommodate maximum 2 electrons.

Also read What is the relationship between a. Energy and wavelength?

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