Post on 13-Sep-2015
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Have a happy an enjoyable moment in chemistry lesson
LOOK AT THIS PICTUREMAN OR WOMAN CANNOT STAY ALONE TO FORM THE STABILITY..
SOIL AND TREE MUST JOIN TOGETHER TO ACHIEVE THE STABILITY
THESE FLOWERS HELD TOGETHER WITH?
STABILITY
Molecule are made up of atoms that bonded together by a chemical bond. But not all atoms prefer to be bonded. Some prefer to be free.Lets study case of neon gas and chlorine gas.NeonGroup 18Has electron arrangement: 2.8Has achieved stable octet electron arrangementDoes not need to form moleculeMonoatomic gas and exist as single atom
Chlorine-Group 17Has electron arrangement: 2.8.7Not achieved stable octet electron arrangement NOT STABLEBecome stable by gaining @ sharing electron with another atom in form of moleculeShare a pair of electron with another Cl atoms to achieve stable has 8 electron valence = octet arrangementDiatomic molecule
We can say that:Neon atom prefer to be monoatomic, whereas Chlorine atoms are prefer to be bonded to another Chlorine atom and exist as diatomic molecule.
Atoms prefer to attain a duplet or octet electron arrangement like a nobel gas.Thus, they form bonds to achieve this stable state
Stability of noble gas
Noble gas like Neon, Argon and etc. are very reluctant to share, gain @ loose electron to form a chemical bond. (*do not form bonds with other atoms)Noble gases are chemically unreactive.All noble gases has 8valence electrons (octet electron arrangement) except for helium which has 2 valence electrons (duplet electron arrangement).Thus, hard for atoms of noble gases to receive electrons from other atoms @ donate @ share its electrons with other atoms.Noble gases cannot combine with one another @ with other elements.
Formation of chemical bondsAll other atoms bond together to become chemically stable.Chemical bond is a strong force of attraction between an atoms @ ions in a substances.There are several conditions for the formation of chemical bonds such as:-the tendency of atoms to achieve a stablevalence electron arrangement-the bonding distance between atoms-the energy requirement for the bonding process
to achieves the stable electron arrangementIonic bondCovalent bondTransfer of e-Sharing of e-
NeutralatomAnion(-)Cation(+)Donates e-Receive e-METAL ATOMSNON METAL ATOMS
++1 electron2+3+++2 electron3 electron
GROUPFORMATIONGroup 1 Group 2Group 13
2--3-+++1 electron2 electron3 electron
GROUPFORMATIONGroup 17 Group 16Group 15
Al2.8.32.83+Donates 3e-Aluminium atom, AlAluminium ion, Al3+
2-Receive 2e-2.62.8Oxygen atom, OOxide ion, O 2-
WHAT IS IONIC BONDS ???
Ionic bonds are usually formed through the transfer of electrons to achieve the stable electron arrangement
e-Donate e-Accept e-Cation (+ve)Anion (-ve)MetalMetalNon-metalNon-metalCation(+ve ion)Anion(-ve ion)Strong electrostatic forces+Ionic bonds
TRANSFERNa2.8.1Cl2.8.7+1-1Na+12.8Cl-12.8.8
ELECTRON TRANSFER FROM METAL TO NON-METAL
STRONG ELECTROSTATIC FORCE
2+2-Magnesium2.8.2Oxygen 2.6Mg 2+2.8O 2-2.8
FORMATION OF IONIC BONDS
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Thanks you for your attentionaja aja fighting!!!!Miss Adda SMT Selangor Sg. Buloh