Orbital and Electronic configuration

Orbital:-

An orbital is a mathematical function that describes the wavelike behavior of an electron, or describes properties characteristic of no more than two electrons in the vicinity of an atomic nucleus or of a system of nuclei as in a molecule. An orbital often is depicted as a three-dimensional region within which there is a 95 percent probability of finding the electron ( Although most people think of an "orbit" in terms of a circle, the probability density regions that may contain an electron may be spherical, dumbbell-shaped, or more complicated three-dimensional forms.

Atomic Number and Isotopes

Atomic Number(z) :-
It is equal to the number of proton in an nucleus of an atom or it is equal to number of electrons in an neutral atom.
For example : Hydrogen has one proton(₁¹H) so its atomic number is 1,similarly for others.


Isotope :-
Atoms having same atomic number and diferent atomic masses(different neutons in their nuclei) are called isotopes so in isotopes element remains same but its atomic mass is different

Mole and Avogadro Number

A mole is the quantity of anything that has .the same number of particles found in 12.000 grams of carbon-12.That number of particles is Avogadro's Number, which is roughly 6.02x10²³. A mole of carbon atoms is 6.02x10²³ carbon atoms.

1 mole of carbon 12 atoms(¹²C)= 12g=6.023x10²³

Atomic weight and Atomic Mass

Mass :-
in actually what the particle in itor actual amount of material contained in it or how hard is to accelerate it or decelerate it ,mass is independent of everything that is gravitational force etc and it remains constant everywhere .It is measure in kg generally but for atoms it is measured in amu(atomic mass unit) which is few grams.

the weight of 1 proton or 1 neutron is approximateley equal to 1 amu

carbon 12(C-12) is taken as benchmark and carbon 12 has mass 12 amu

Atomic weight :-

 weight is the total amount of gravitational force exerted by gravity in it.So even on earth we have difference in our weights due to difference in gravitational forces .For atoms atomic weight is also calculated in "amu" but it is weighted average across many isotopes like we can take example of carbon it has isotopes like carbon 12,carbon 13,carbon 14 and the weighted atomic weight comes out to be 12.011 amu of all these isotopes as carbon 12 is most abundant in earth