Structure and bonding

Here my aim is to give you  or share you my knowledge about structure and bonding.So let's start.
In chemistry, we can name all the types of  bonding as chemical bonding.

Chemical bonding:

Chemical bonding can be defined as the attraction between the atoms in order to minimize the energy.So why do they like to like to be in least  energy level, It is because the fact that they want to be stable.If they wanna be stable they  should be at least energy level the chemical bonding thing is happened to minimize the energy Orbital hybridization is also a  scenario which happen in order to minimize energy.

Now let's find out the situations where the bonding occurs in between atoms.

In order to have chemical bond attraction forces between two atoms must be greater than their repulsive forces.This is a must factor.

First situation:

When  two atoms have  an unpaired  electrons in their  orbitals.

Second situation:

When one atom have an empty orbital while other atom have completely filled orbitals.

Now let's discuss about non-bonding situations.

Non-bonding situations:

  • When  the orbitals of both the atoms are completely filled.

  • When  orbital of one is completely filled and other atom have hafl filled orbital.

In case of non-bonding situation repulsive forces between two atoms are greater than their attraction forces.

In chemistry, you have mainly three types of bonds.Namely they are,

  • Covalent bond
  • Ionic bond
  • Dative bonds.
  • Metallic bonds.

And you have two types of bonds for covalent bonds.They are,
  1. Non-polar covalent
  2. Polar covalent.

Well, now we know how to determine whether  a chemical bond is available or not.But still we don't know which types of bonds would be formed if all those above mentioned requirements are fulfilled. There is an easy way for that.It is by comparing electronegativity difference between two atoms.

Now let's discuss about the covalent bond.

Covalent bond:

This bondage is in between two non-metal atoms.In this type of bond electron pair is common to both of the atoms.So how does that happen? Do you have any idea about that.In order to have a electron pair common for both the atom electron cloud  of both atoms should be overlapped that is when electrons are common for both the atoms(keep in mind that electrons are behave as cloud and particle in nature at the same time).If you confuse with that  thing remeber it like this, electron is a cloud which have their particles inside that cloud.
There are two type of overlappings which cause to have a covalent bond.Namely they are,

  1. Linear overlapping
  2. Lateral overlapping.

Linear overlapping:

In this type of overlapping  high density electron cloud is right in the middle of two atoms.When there is linear overlapping the type of bond  formed is $sigma$ bond.This is catogarized by considering overlapping factor.And this happen only in covalent bond.So guys don't confue this fact by thinking this as another sub bond in covalent bond like polar covalent bond,  $sigma$ bond  comes to the act only when we consider overlapping factor.So in case of  linear overlapping it is $sigma$ bond.

Linear overlapping is occur when,

  • S-P orbitals overlap

  • P-P orbitals overlap

Now move to next type of overlapping.

Lateral  overlapping:

Here the high-density electron cloud is not right in the middle but it is contaminated in upper end and lower end of the space in between two atoms. I know it's little bit complicated to imagine it. So take a look at the follow image.

Lateral overlapping occuronly in between P orbitals. Because of that $pi$ bond can be obtained by lateral overlapping of two P orbitals.

 Dative bond:

      This bond is formed by overlapping of an atomic orbital containing a lone pair of electrons while the other atom is with an empty orbital for their valence shell.At this scenario the spcies which dontate the electron is named as donor group while the revceiever is named as acceptor group.`

Ionic bond:

This bond is formed due to the electrostatic interaction between positive and negative ion that are formed when the valence electron of one atom is given to th other atom during the formation of between this two atoms,right I hope you got it. Just to remember here the electronegativity difference between teo atoms is greater than 2.1

to discuss few properties of this type p f bond we can take our example as$NaCl$.When we consider about solid state of$Na^+$ and $Cl^-$  are attracted electrostatically and packed in definite pattern.Therefore can't move they are isolated into one position.The only they can do is just vibrating here and there.Since the ions can't move  solid state of ionic bond can't conduct electricity.Because  that is the main property that should prevail in order to conduct electricity.But in liquid  and in molten state $NaCl$ has mobile ions because of that fact at those two states.

Metallic bond:

The electrons of valency shell og metallic atoms are loosely bonded to the atom. Therefore, there is a tendency for metallic atom to release the electrons and exist as positive ions. And due to that there you have positive ions in electron sea of the system.Why I say system here? Because  you need to consider whole electron cloud.So finally the bond is formed between the positive ions and electrons.That type of bonds are named as metallic bonds.

Now let's discuss  the factors affecting for the strength of metallic bond

  • Number of electrons contribute to metallic bond - strength increases when no. of electrons increases.
  • Size of the metal ion - bond strength increase when size decreases
  • Charge of the metallic ion-   bond strength is higher when charge is high.

So across the period metallic bond strength increases so that softness of metal decreases which means metals going to be more harder.How about the reactivity? Make a guess.Reactivity decreases because metallic bond strength increases.Is it confusing? Just think like this, if anything is combined rigidlya is it harder to  separate it compared to one which is less rigid than that? Probably is it is harder.So reactivity is like that.

Well, I hope you have a good knowledge in bonding. If you have any doubt about this feel free to comment.

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