Embed Size (px)
Citation preview
SUBSTANCE
ELEMENT COMPOUND
ATOM MOLECULEMOLECULE ION
•Pure metal
•Noble gases
•He, Ne, Ar
•Cu, Mg, Ag
•Two similar atoms of non metal element share their valence electron to achieve octet/duplet electron arrangement (group 15, 16 and 17)
•N2, O2, Cl2,
Br2, I2, H2
• Two different non metal atoms of element share their valence electron to achieve octet/duplet electron arrangement
( between group 15, 16 and 17)
•CO2 , H2O , SO2
•Metal atom (group 1, 2, 13 release electrons to form positive ion).
•Non metal atom (group 15,16,17 receive electrons) to achieve octet/ duplet electron arrangement
NaCl , CuSO4
ELEMENT
A pure substance cannot be subdivided into any simpler substances by physical or chemical process
COMPOUND
A substance that contain two or more different types of elements that are chemically bonded together
Na
DEVELOPMENT OF ATOMIC MODEL
DALTON •Idea of atom
THOMSON•Negatively charged electron•Positively charged sphere
RUTHERFORD
•Nucleus at the centre of atom contains positively charged proton
•Electrons move outside nucleus
CHADWICK ATOMIC MODEL
BOHR
CHADWICK ATOMIC MODEL
ELECTRON ARRANGEMENT FOR
AN ATOM
Subatomic Subatomic ParticleParticle
Relative Relative MassMass
Relative Relative ChargeCharge
Position
ProtonProton
ElectronElectron
NeutronNeutron
11
1/18401/1840
11
+1+1
-1-1
00
Proton number : Total number of proton in the nucleus of an
atom
Nucleon number : Total number of proton and
neutron in the nucleus of an atom
In the
nucleus
In the shells
Standard Representation Of An Element
A
ZX
X - Symbol of an element
A – Nucleon number of atom X
Z – Proton number of atom X
ATOM• The smallest neutral particle of an element• Normally pure metals, noble gases, a few non metal
such as carbon and silicon
Na
Sodium ELEMENT
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
NaNa
Sodium ELEMENT Sodium ELEMENT Sodium ELEMENT
Sodium ATOM
SODIUM ATOM
NaNa
Electron arrangement of sodium atom is 2.8.1
Sodium element consist with many sodium atoms
Electron arrangement of sodium element is 2.8.1
NaNa NaNa NaNa
NaNa
NaNa
NaNaNaNaNaNa NaNa
NaNa NaNa NaNa NaNa
SODIUM ELEMENT
2311Na Standard Representation For Sodium Element
The Structure Of Sodium Atom
11p + 12n
The Electron arrangement Of Sodium Atom
Na
Number of proton
Number of electron
Number of neutron
Proton number
Nucleon number
Electron arrangement
Number of valence electrons
Group
Number of shells
Period
2311Na 11
11
12
11
12
2.8.1
1
1
3
3
Electron Arrangements In Some Of Inert Gases Atoms
All Inert Gases atoms have eight valence electrons (octet) except Helium which is stable.
Helium atom has two valence electron (duplet) Why?
Helium2
(Duplet)
Neon2.8
(Octet)Argon2.8.8
(Octet)
He Ne Ar
EXAMPLE : PERIOD 3 ELEMENT
ELEMENT Na Mg Al Si N S Cl Ar
PROTON NUMBER 11 12 13 14 15 16 17 18
ELECTRON ARRANGEMENT
2.8.1 2.8.2 2.8.3 2.8.4 2.8.5 2.8.6 2.8.7 2.8.8
I
2 13 14 15 16 17
18
1
2
3
4
5
6
GROUP
PE
RIO
D Inert Gases in The Periodic Table Of
Element
Why are these elements located in Group 18?
•Each atom from group 1-17 elements has 1,2,3,4,5,6 and 7 valence electrons respectively.
•They are not stable. Each atom does not achieve octet electron arrangement.
•How do these atoms achieve stable octet/duplet electron arrangement?Atoms form CHEMICAL BONDS to achieve a stable duplet or octet electron arrangement.•Bonds are formed when two or more atoms of elements are bonded together.
• There are TWO TYPES OF CHEMICAL BOND:
1. IONIC BOND ( Particles form are positive ion and negative ion)
2. COVALENT BOND.( Particle forms is neutral molecule)
