Chemical bonding, Biology

Assignment Help:

Chemical bonding : The present matter of earth contains atoms bound in groups of two or more called molecules. Their binding capacity is called chemical reactivity; It depends upon the number of electrons in their outermost shell. When the number of shells  is more than one maximum seven the first shell nearest to the nucleus can have maximum two electrons the second one can have maximum 8,third one as many as 18 fourth 32,fifth 32,sixth 18and seventh only two. Whichever it may be the outermost shell can never have more than 8electrons.Thus the presence of 8 electrons in the outermost shell represents the stability of an atom. In chemical bonding, the reactive atoms tend to gain stability either by covalent bonds electrons of their outermost shells, or by transferring ionic or electrovalent bonds electrons from one to the other. For instance, a molecule of water is formed by covalent bonding of two hydrogen atoms with an atom of oxygen atom has two electron shells. That of hydrogen atom has a single electron instead of the maximum two it can have. Similarly, the outermost shell of oxygen has only 6 electrons instead of 8 it can have. Obviously, an oxygen atom binds with two hydrogen atoms to complete the electron the electron number of8 in its outermost shell, while each hydrogen atom completes the number of two electrons in its shell, all by mutual sharing.

414_hydrogen atom.jpg

1905_helium.jpg 857_sodium atom.jpg62_calcium atom.jpg

In another example, an atom of sodium combines with an atom of chlorine to form common salt (NaCI) sodium atom contains 11 electrons in 3 shells (2,8,1,) Chlorine atom contains 17 electrons in 3 shells(2,8,7,)  To gain stability, chlorine atom takes up the lone electron of the outermost shell of sodium atom, while the latter easily loses this shell. Thus due to change in their electrons both atoms become electrically charged ions. Losing of an electrons by an atomic such electrovalent bonding is called its oxidation, and gaining of an electron by an atom is called its reduction.

1537_water molecule.jpg


Related Discussions:- Chemical bonding

Name the implant failures, Implant failures On the basis of the stage w...

Implant failures On the basis of the stage when problems occurs implant failures can be classified as : i) Before Abutment Connection. ii) During Abutment Connection.

Define the term- adaptation, Define the term- Adaptation The terms sco...

Define the term- Adaptation The terms scotopic and photopic vision are relative to the lighting conditions of an individual place. Light adaptation is a very quick process and

Explain about pergingival regenerative therapy, Explain about Pergingival R...

Explain about Pergingival Regenerative Therapy In case of one stage implants being treated or when the prosthesis has to be maintained a  Pergingival Regenerative Therapy is d

Describe class agnatha in details, Describe Class Agnatha in details? C...

Describe Class Agnatha in details? Class Agnatha takes its name from the Greek word "gnathos," which means jaw, and "a," which is the prefix for "without." These jawless fishes

Advantages of vegetative propagation, Advantages of vegetative propagation ...

Advantages of vegetative propagation Vegetative propagation helps to maintain fixed qualities and characteristic features of the parent plant. For Example in ornamental p

Explain assessment of iron status - serum ferritin, Explain assessment of i...

Explain assessment of iron status - Serum Ferritin? Serum Ferritin: This method is indicative of iron stores. As we know, a long term negative iron balance first results in dep

What is the difference between xylem and phloem, What is the difference bet...

What is the difference between xylem and phloem? Both xylem and phloem are vascular tissues found in a plant. Xylem is a tubular structure, which is liable for water transport

Determine the major demographic processes, Determine the major demographic ...

Determine the major demographic processes? There are five major demographic processes, which are continually at work within the population namely, fertility, mortality, marriag

Bacteria, Bacteria The study of bacteria is called bacteriology. Bacte...

Bacteria The study of bacteria is called bacteriology. Bacteria are unicellular organisms and possess a distinct cell wall. They are included in kingdom Prokaryote. The bacter

Bees, is there a difference between the giant asiatic bees apis dorsata and...

is there a difference between the giant asiatic bees apis dorsata and Philippine giant bees apis breviligula

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd