Chemical Bonding Gghs Naiabadi

PRESENTED BY: MRS. SUNITA SHARMA GGHS NAI ABADI HOSHIARPUR

A chemical bond is an attraction between atoms brought about by a sharing of electrons between to atoms or a complete transfer of electrons.

TYPES OF BONDING

IONIC

COVALENT

POLAR COVALENT

When two atoms that can chemically react with each other approach each other, it is the outer shell electrons, farthest from the nucleus and hence less attracted to its nucleus, that interact with the outer shell electrons of the other atoms in the process that will create a chemical bond between the elements.. IT IS THE OUTER SHELL ELECTRONS THAT ARE MOST IMPORTANT IN THIS PROCESS.

If an atom gives up an electron to another atom, then they have an ionic bond. Ionic bonds arise from elements with low electronegativity (almost empty outer shells) reacting with elements with high electronegativity (mostly full outer shells). In this case there is a complete transfer of electrons.

A well known example is table salt, sodium chloride. Sodium gives up its one outer shell electron completely to chlorine which needs only one electron to fill its shell. Thus, the attraction between these atoms is much like static electricity since opposite charges attract.

Some examples of IONIC BONDING

Covalent bonds involve a complete sharing of electrons and occurs most commonly between atoms that have partially filled outer shells or energy levels. Thus if the atoms are similar in negativity then the electrons will be shared. Carbon forms covalent bonds.

Hydrogen gas forms the simplest covalent bond in the diatomic Hydrogen molecule. The halogens such as chlorine also exist as diatomic gases by forming covalent bonds. The nitrogen and oxygen which makes up the bulk of the atmosphere also exhibits covalent bonding in forming diatomic molecules.

SINGLE COVALENT BOND

TRIPLE COVALENT BOND

DOUBLE COVALENT BOND

Covalent Bonds in which the sharing of the electron pair is unequal, with the electrons spending more time around the more nonmetallic atom, are called Polar covalent bonds. In such a bond there is a charge Separation with one atom being slightly more positive and the other more negative, i.e., the bond will produce a dipole moment.

Examples of other molecules that have polar covalent bonds are Peptide Bonds & Amines.

In addition to Ionic, Covalent and Polar Covalent Bonds chemists often recognize another type of bond called a Hydrogen Bond. A hydrogen bond is formed when a charged part of a molecule having polar covalent bonds forms an electrostatic (charge, as in positive attracted to negative) interaction with a substance of opposite charge.

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