Bonding in Molecules

Molecule is a group of two or more atoms which are combined from chemical bond.
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structure of atom

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Chemical bond=atoms are present in molecule of a compound attached from a force, that force called chemical bond. There are three types of bond

1. Electro-valent bond or ionic bond

2. Covalent bond

3. Coordinate bond

Ionic bond=ionic bond is made from electron transfer between atoms. When a electron transfer from one atom to other atom a atom which donate electron has positive charge and the atom which accepts the electron has negative charge. These opposite charged atoms connect by electrostatic force this force called electro-valent bond. And the number of exchanged electron called these atoms electro valence.

Characteristics of electro-valent compounds=

1. These compounds are hard and brittle.

2. These are non volatile on normal temperature and pressure.

3. To remove ion of the compound we need high energy so melting point is high.

4. In solid state the compound is non conductor but in fused state this is conductor.

5. These compounds do not show isomerism.
Covalent bond== this bond is made from partnership of same electrons between atoms. The compound has this type of bond called covalent compounds.

When two atoms share 1.2 or 3 electrons then the bond calls single bond. Double bond or triple bond.  Firstly Lewis describes them in 1919.

Characteristics of covalent compounds=

1.At normal temperature covalent compounds available in gas or liquid state because there molecules combined from Vander Waals force.

2.There are three type of covalent compounds

(a)Soft and evaporative solid there crystal’s unit is molecule and they combined by Vander Waals force.example-I_2, S₈  

(b) The solid which has crystal’s separate layers. Example-graffiti.

(c)The solids in all atoms combined from covalent bond and make a giant molecule. Example -SiC.

3.There boiling and melting point are low.

4.These compounds are non conductor.

5.Covalent bonds are rigid and directional.

6.The molecules of these compounds participate in chemical reaction. The speed of reaction is slow then ionic reaction. 

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 Coordinate bond=according to TM Lowry and NV sidwick, coordinate bond is a special type of covalent bond. in this bond two atoms attached by one electron pair, but the electron of pair given by only one atom. a atom which outer orbital is full gives electron pair to other incomplete atom. the atom who give electron call donor and other atom who take call acceptor. this bond is showed by arrow.

example=

Characteristics of coordinate bond=

1.this compounds are found in all states.

2.these are non conductor.

3.there dielectric is high.

4.this compounds gives molecular reactions.

Read about my other article about biomolecule carbohydrate on this link-

CARBOHYDRATE

singlet linkage= This type of bond is defined by sudden. according this a tom which outer orbital is full donate his single electron from loan pair electron to two atoms it show by half  headed arrow.

overlapping between atomic orbitals=

axial overlapping=in this type atoms overlaps from axis and make sigma bond. example-s-s overlapping.

sidewise overlapping=by this type pay bond makes this  only makes in sigma bonds presence  its a weak bond.example-Py-Py overlapping.

hybridisation- when two atomic orbitals  which energy level are almost equal combines and make new orbitals of same energy then these new orbitals calls hybridised orbital and this is hybridisation.

characteristics of hybridisation=

1.in this atoms  different orbitals of external classes take part.

 2.only orbitals which has almost equal energy take part in this.  3.number of new orbital is same of orbital which combines

 4.only atomic orbital take part in that, not electron.

 5. the bond makes hybridisation is strong.

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Questions related to bonding in molecules

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STRUCTURE AND FUNCTION IF VITAMIN