Atom and molecules l Defination, History, Parts of Atom


Atom -:Molecular unit of any matter present in this entire universe is called atom.  Except only energy, everything else in the world is made up of these atoms. "

Let me tell you more here that atoms themselves are made up of three types of sub-atomic particles .

These three sub-atomic particles are Electron, Neutron and Proton.

Structure of atom -: 
As I mentioned above, an atom is mainly made up of Electron, Neutron and Proton.  So first of all we have to know about these three corpuscles.

1. Electron -: electron is a sub-atomic corpuscle which is the fundamental unit of negative charge.  This corpuscles transport the negative charge in metals.

 2.Neutron-:  Neutron is a sub-atomic corpuscle without any electrical energy.  This corpuscle is present in any other substance except hydrogen.  Its mass values ​​are the same with Proton.

 3.Proton -: Proton is a sub-atomic corpuscles, which transport a positive charge in one atom.  The amount of energy present in the Proton is the same with the electron, but unlike the electron, this energy is present inside it as a positive charge.

Proton and Neutron mainly give the center of the atom its correct form.  The nucleus of any atom made of Proton and Neutron is known as Nucleus.

Nucleus -:
The electrons around the nucleus revolve like the planets present in the solar system.  Here, let me tell you more that this electron keeps revolving around a special class Nucleus, which we also called Shell.  In an ordinary atom, the number of both electron and proton remains mostly the same.  However, from time to time there may be changes in these.  Here, let me tell you more that the number of Neutron also remains the same as the rest of the corpules.

Some term related to atom and molecules -:
1.Atomic Number (Z) -:
 If I say in simple language, Atomic Number is the total number of protons present in the substance.  Mostly, the number of electrons, Neutron and Proton remains the same in an atom . But here Atomic number (Z) separates any two substances from each other.  So that we can identify any substance well.  For example, if I take the oxygen atom, the atomic number (Z) of oxygen is 8, because only 8 protons are present inside it.

 2. Mass Number (A) -: 
For any substance, his mass is very full of gravity.  Because of this we can easily make very complex mixtures in chemistry.  So, the mass number (A) is made up of the total number of Neutron and Proton present in the atom.  Although there is also the participation of Electron here, but due to this very small participation, it is not counted in the Mass number (A).

 Here if you know the Mass Number, then you will be able to easily find out the number of Electron, Neutron and Proton in any substance.  For example, if I take the Lithium atom, you will see A = 7 and Z = 3 in it.  Here if you do A-Z (7-3), you will get 4 digits (7-3 = 4) which will be the number of Neutrons.  Therefore, if you remember this formula of N = A-Z, you can easily understand the atomic structure of any substance.

 3. Isotopes -:
 In simple language, Isotope is a type of substance (more than one), in which the number of Proton is the same, but the number of Neutron is not the same.  It is a different form of a substance.


 

Molecules
A molecule is a corpuscle made up of many atoms, which is the smallest unit of any chemical reaction (fundamental unit of a chemical reaction)".

Most molecules are formed by a special type of chemical bond made of atoms.  These bonds do not form molecules, but they also transport electrons.  These bonds combine with molecules of other substances to form a new compound.  The structure and size of each Molecule present in the world is different.  Usually molecules are present around us in the form of solid, liquid and gas.  For example, water (H2O) is also a type of molecule.

So, friends, in this way you will find many types of molecules in this world.  Because everything in the world is made up of atoms (other than energy) and atoms are made of atoms.


Difference between atoms and molecules

Now that you have learned about both atoms and atoms, then the question must surely arise in the mind, what is the difference between atoms and atoms?  So, let's try to find the answer here.

 Mostly these two corpuscles are very small in size.  So we cannot see them with open eyes without any equipment.  We cannot see any kind of bonding inside any atom.  But in a molecule we can easily see many types of bonding.

 Here, let me tell you more, if two similar types of atoms also meet, then they can form many types of molecules from time to time.  For example, two oxygen atoms form O2 and three oxygen atoms form ozone (O3).  But if the same type of molecule is found together, then both of them will form the same type of compound.

 Mostly you have seen that the atoms which are there are quite unstable.  Because the electrons inside the atoms make it very unstable. Usually due to the imbalance in the number of electrons in the atoms, they are not stable.  But due to electron sharing of atoms in a molecule, they are mostly stable.  Therefore, if you look at the structure of any molecule properly, then you will definitely be able to see its stability.