CHEMBONDING ELECTRICAL ENGINEERING BY PP

IMPORTANT LESSONS

1. CHEMICAL BONDING WELCOME TO MY PRESENTSTTION HELLO EVERYONE Shall we start? OR Shall we not start? Your presenter: SCOTFIL C. MCCREA

2. CHEMICAL BONDING TABLE OF CONTENTS CHEMICAL BONDING TABLE OF CONTENTS 1 min . INTRODUCTION DIFFERENT TYPES OF BONDING 1.) ICONIC BONDING or POLAR BONDING 2.) COVALENT BONDING or HOMOPOLAR BONDING 3.) METALLIC BONDING 4.) RESIDUAL BONDING and VAN DER WAALS BONDING CONCLUSION REFERENCE ...

3. HGGG CHEMICAL BONDING INTRODUCTION . 2 min CHEMICAL BONDING INTRODUCTION ... The structural principle in crystals, there are two aspects to be discussed:  The geometry of the molecular arrangement; The thermo dynamic factor which decides such arrangement.  The second aspect is related to the nature of chemical bonding, these are the four types of bond, namely: Ionic bond Covalent bond Metallic bond Van Der Waals bond

4. HGGG CHEMICAL BONDING IONIC BONDING . 3 min CHEMICAL BONDING: IONIC BONDS ...  Negatively and positively charged particles attract each other.  In atoms, positive charged particles (protons) attract negatively charged particles (electrons).  Positively charged cations attract negatively charged anions producing ionic bonds in minerals.  The elements bond together to form compounds, all are electrical.

5. HGGG CHEMICAL BONDING IONIC BONDING . 4 min CHEMICAL BONDING: IONIC BONDS ...

6. HGGG CHEMICAL BONDING IONIC BONDING . 4 min CHEMICAL BONDING: IONIC BONDS ...

7. HGGG CHEMICAL BONDING COVALENT BONDS . 5 min CHEMICAL BONDING: COVALENT BONDS ...  Giving up or gaining electrons to become ions, atoms may become stabilized by sharing electrons.  The sharing of electron between the atom is known as covalent bonds. If the sharing is complete the bond is 100% covalent.  Covalent bonds are strong bonds. Examples: Diamond, pure Carbon

8. HGGG CHEMICAL BONDING COVALENT BONDS . 6 min CHEMICAL BONDING: COVALENT BONDS ... - Silicate ceramics EXAMPLES -Glass

9. HGGG CHEMICAL BONDING METALLIC BOND . 7 min CHEMICAL BONDING: METALLIC BONDS ...  Metals hold on to their valence electrons very weakly . P ositive ions (cations) floating in a sea of electrons.  Electrons are free to move through the solid.  Metals are good conductors of electricity.  Crystals with this type of bonding are called metallic crystals  Some metallic elements atomic structure is more complex, with more than one type of bond occurring between the atoms.  Three ways in which the ions of most metals are packed together to form crystals  Three method of stacking spheres of equal size: cubic close packing Body centered cubic close packing Hexagonal close packing

10. HGGG CHEMICAL BONDING CUBIC CLOSE PACKING . 8 min METALLIC BONDING: CUBIC CLOSE PACKING ...  Sphere represent identical metallic ions.  Each sphere touches three in the layer above or below.  A succession of three layer can be placed one on top of the other in different positions.  The fourth layer repeats the position of the first.  The patterns repeats after every third layer.

11. HGGG CHEMICAL BONDING CUBIC CLOSE PACKING . 9 min METALLIC BONDING: CUBIC CLOSE PACKING ... EXAMPLES -Beryllium -Magnesium

12. CHEMICAL BONDING BODY CENTERED CUBIC PACKING . 10 min METALLIC BONDING: BODY CENTERED CUBIC PACKING ...  Sphere represents identical metallic ions.  Spheres lie at the corners of cube and with one sphere at the center of each cube.  Each sphere touches eight others ,and the packing is not as close as in the other two types.  Close packed layers are absent.  Metal with this type of structure is harder and more brittle. ( do note that brittle means fragile )  Iron has this structure at normal temperature. At h igh temperature, it possesses the cubic close packed structure and becomes malleable as a consequence. ( do note that malleable materials can be molded out of shape without breaking . )

13. CHEMICAL BONDING BODY CENTERED CUBIC PACKING . 11 min METALLIC BONDING: BODY CENTERED CUBIC PACKING ... EXAMPLES -iron -Chromium Carbonyl

14. CHEMICAL BONDING HEXAGONAL CLOSE PACKING . 12 min METALLIC BONDING: HEXAGONAL CLOSE PACKING ...  This structure contains close packed layers with the canters of identical sphere laying at the corners equilateral triangle.  Adjoining layers are displayed so that any sphere lies above or below three spheres in the layer next in to it, with every alternate layer identical.  The structure repeats after every second layer instead of after every third as in the cubic close packing.

15. CHEMICAL BONDING HEXAGONAL CLOSE PACKING . 13 min METALLIC BONDING: HEXAGONAL CLOSE PACKING ... EXAMPLES -Titanium -Zirconium Dioxide

16. CHEMICAL BONDING VANDER WAALS BONDING . 14 min CHEMICAL BONDING: VANDER WALLS BONDING ...  It has weak force of attraction between the ions or atoms of all solids.  Bond is different from all the others, it is rarely responsible for the coherence of any common substance. ( note that coherence means the ability to have a constant phase relationship of waves. )  Residual bond effect is often masked in structure, where ionic covalent or metallic bonding already occurs.  The only entirely solid with Vander walls bonding are inert gases (neon, argon, etc.) in the solid state. NOTE: Van Der Waals bonding is named after the Dutch physicist Johannes Diderik van der Waals , who in 1873 first postulated these intermolecular forces in developing a theory to account for the properties of real gases.

17. CHEMICAL BONDING VAN DER WAALS BONDING . 13 min CHEMICAL BONDING: VANDER WALLS BONDING ... EXAMPLES -Selenium -Antimony

18. CHEMICAL BONDING REFERENCES . 13 min CHEMICAL BONDING: REFERENCES ...  BOOKS Jak tareen & TRN kutty:2011 A basic course in crystallography University press (India) limited Rutley‘s text book of mineralogy  WEBSITE F:\Chemical bond - Wikipedia, the free encyclopedia.mht

19. THAT IS ALL FOR LISTENING