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CHAPTER 2
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2.1 MATTER
Most of the things thatwe could see in this world
are MATTER
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What is matter?
Matter means:- anything that occupies space &
has mass- made up of tiny & discrete
particles- Exist as element@compound
Next
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A pure substance whichcannot be broken down into
simpler substance physically& chemically
Matter
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Usually made up of
two or more elements
which are chemically
bonded together
Matter
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1. Matter are made up of tiny &discrete particles
2. Size of particles are veryminute ~~ 1x 10-7cm
3. Consist of atoms, moleculesions
Next
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Lets see the particles inbromine liquid
Particle theory
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The smallest particle of an elementand not breakable anymore.
Examples:Atom of hydrogen
atom of magnesium
atom of oxygen
atom of chlorine
H
Mg
Cl
O
Particle theory
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A group of two @ more atoms,which might consist of:
one type of element (Element)
@ different types of element(Compound)
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Examples of element molecules:
Molecule of hydrogen gas
Molecule of oxygen gas
Molecule of chlorine gas
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Examples of compound molecules:
Molecule of water, H2O
Molecule of ammonia, NH3
Molecule of ethanol, C2H5OH
N
C C
Particle theory
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Ions are atoms which havecharge
Positively-charged ion /cation(loss e-)
Negatively charged ion / anion (gain e-)
+
-
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Hydrogen atom Hydrogen ion
Magnesium atom Magnesium ion
Oxygen atom Oxide ion
Chlorine atom Chlorine ion
Particle theory
H+H Lose electron
Mg2+Lose electronMg
O2
-
Gain electronO
Cl-
Gain electronCl
Symbol of element
Examples of ions:
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Kinetic means motion (move) Kinetic theory states that:
1. Matter consist of particles whichconstantly moving
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2. particles move in random motion ,
collide with each other
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A. substance is cooled,
- particles lose kinetic energy- move slower
B. substance is heated,- particles gain kinetic energy- move faster
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Heat energy makes particlesmove faster!!!
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Experiment which supports
the kinetic theory:
Investigating the diffusion of
particles in asolid, liquid and gas
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What is diffusion ?
How diffusion supports the
kinetic theory ?
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Diffusion happens anyway thatdifferent concentration
of particles
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Is the rate of diffusion
different in solid, liquid,and gas state?
Lets get an experimentto check it out!!!
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Diffusion in Solid (membrane)
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Diffusion in Liquid ( )
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Diffusion in Gas (air)
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Diffusion affected by Density
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The conclusion is.
Diffusion happens in solid, liquid,and gas states
Diffusion occurs slowest in solid,faster in liquid and fastest in gas
Diffusion occurs faster in subtance
with lower density Diffusion supports kinetic energy
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The Physical States of Matter
Solid
Liquid
Gas
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The Arrangement of Particles
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The Shape & Volume of Particles
Th M & E C f
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The Movement & Energy Content of
Particles
Th A F
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The Attraction Force
between Particles
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The Physical Changes of Matter
Freezing
GasLiquid
Solid
MeltingSublimation
Boiling
Condensation
Sublimation
D t i th
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Determine theMelting Point of Naphthalene
Melting point
the temperaturewhich a solid
becomes liquid
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Diagram of heating naphthalene
Q1-Q4 Q5-Q7
Solid naphthalene
Water
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Heating curve of naphthalene
A
CB
D
Temperature / C
Time / minute
79C
Q1-Q4 Q5-Q7
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What is the Melting point?A: 79C
What is the physical state at B-C?A: solid and liquid
Where is point that Melting process started?
A: B
Where is point that Melting process ended?A: C
graph apparatus
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Why the curve of heating has no change at B-C?A: because the heat energy absorbed by
naphthalene molecules to overcome the forces ofattraction to becomes liquid
Why solid naphthalene heated in water ?
A: to ensure a uniform heating
If the melting point of Substance X is 123C, canwe still use water as medium? Why?
A: No. Because its melting point is higher thanthe boiling point of water. We can use oil bath toreplace water. graph apparatusPhysical changes
D t i th
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Determine theFreezing Point of Naphthalene
Freezing point the
temperature which a solutionbecomes solid
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Cooling curve of naphthalene
Q1-Q4 Q5-Q7
79C
E
Temperature / C
G
H
Time / minute
F
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Is the freezing point same with the Melting point?A: Yes, both are 79C
What is the physical state change in thisexperiment?A: Liquid naphthalene changes to solid
Where is the point thatfreezing process started?A: F
Where is the point thatfreezing process ended?A: G
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Why the curve of heating has no change at F-G?
A: because the heat energy released during
formation of bonds is equal to the heat released tosurroundings
Why liquid naphthalene in the boiling tube is cooled
inside a conical flask?
A: to ensure a uniform cooling
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Different solution has differentboiling point & freezing point
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Diagram of cooling naphthalene
Q1-Q4 Q5-Q7
Liquid naphthalene
Empty conical flask
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2.2 ATOMIC STRUCTURE
Th Hi t i l D l t Of
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The Historical Development OfAtomic Models
John Dalton
imagine atom as aindivisible tiny ball
J.J. Thomsondiscovered electrons
Ernest Rutherford
discovered proton,mass of atom concentrated in nucleus
Neils Bohrproposed the electrons
move in shells around the nucleus James Chadwick proved the existence
of neutrons
S b i P i l I A A
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Subatomic Particle In An Atom
S b i P i l I A A
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Subatomic Particle In An Atom
Proton
Neutron
Electron
S b t i P ti l I A At
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Subatomic Particle In An Atom
Proton Electron
Neutron
Nucleus
of atom Electron
shells
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S b t i P ti l I A At
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Subatomic Particle In An Atom
S b t i P ti l I A At
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol
Electric Charge
Relative MassLocation
S b t i P ti l I A At
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p
Electric Charge
Relative MassLocation
S b t i P ti l I A At
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n
Electric Charge
Relative MassLocation
S b t i P ti l I A At
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge
Relative MassLocation
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1
Relative MassLocation
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0
Relative MassLocation
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative MassLocation
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1Location
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1Location
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 0Location
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 0Location in the
nucleusatom
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 0Location in the
nucleusatom
in thenucleusatom
Subatomic Particle In An Atom
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Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 0Location in the
nucleusatom
in thenucleusatom
Electronshells whicharound the
nucleus atom
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Symbol of Element
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40
20CaNucleon number
Proton number
Symbol of Element
-When an atom is neutral ,(1.refer ions)
its number of proton = e-
- number of protons = 20
so number of elecrons = 20- 2.electron configuration = 2.8.8.2
valence electron = 2
Symbol of element
3.Next
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Electron Configuration
Also known as electron arrangement
How electrons fill into the shells?
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Helium He
Proton number 2
2
Hydrogen H
Proton number 1
1
Lithium Li
Proton number 3
2 . 1
Beryllium Be
Proton number 4
2 . 2
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Boron B
proton number 5
2 . 3
Carbon C
Proton number 6
2 . 4
Nitrogen N
Proton number 7
2 . 5
Oxygen O
Proton number 8
2 . 6
Fluorine F Neon Ne
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Proton number 9
2 . 7
Proton number 10
2 . 8
Sodium Na
Proton number 11
2 . 8 . 1
Magnesium Mg
Proton number 12
2 . 8 . 2
Aluminium Al
P t b 13Silicon Si
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Proton number 13
2 . 8 . 3
Proton number 14
2 . 8 . 4
Phosphorus P
Proton number 15
2 . 8 . 5
Sulphur S
Proton number 16
2 . 8 . 6
Chlorine Cl Argon Ar
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Chlorine Cl
Proton number 17
2 . 8 . 7
Argon Ar
Proton number 18
2 . 8 . 8
Potassium K
Proton number 19
2 . 8 . 8 . 1
Calcium Ca
Proton number 20
2 . 8 . 8 . 2
C l i
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Conclusion:
1st Shell: max 2 e-2nd Shell: max 8 e-
3rd Shell: max 8 e-
1) Because they have the same
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) ynumber of orbits, they have 2
orbits / electron shells2) Group 1 is alkaline metals,
hydrogen is a type of gas /hydrogen is not alkaline metal3) They have stable// electron
arrangement (Helium, pn=2
duplet, Argon, 2.8.8 octet)
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4) Li, Be, B, C, N,O,Br, Ne
5) i) K, Ca, Mgii) C, S, Cl
ARRANGEMENT OF SHELLS IN AN ATOM
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NUCLEUS
2 ELECTRONS
8 ELECTRONS
8ELECTRONS
18 ELECTRONS
1
23
4
Electron arrangement in the
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Electron arrangement in the
carbon atom
C12
6
proton number = 6
number of protons = 6
number of electrons = 6
2 . 4
= electron
nucleus
Number of valence
electrons = 4
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23
11 Na
2 . 8 . 1
number of protons = 11
proton number = 11
number of electrons = 11
= electron
Nucleus
Number of valence
electrons = 1 Symbol of element
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Draw & state the electron arrangement of
the elements below
X
15
7 Y
24
12 Z
39
19
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Let us learn somechemical words !!
P t b ( )
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Proton number (p) number of protons in the nucleus of atom
Nucleon number (p+n)total number of protons and neutrons inthe nucleus of atom
3. Valence electron the electrons in the outermost shell
4. Electron configuration arrangement of electron
Repeat them !!
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epeat t e !!Proton number
number of protons in the nucleus of atomNucleon number
total number of protons and nucleons
in the nucleus of atomValence electron
the electrons in the outermost shell
Electron configuration arrangement of electron
T h !!!
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Try this out!!!
Q1 Fill in the blanks
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Elements Proton
Number
Nucleon
Number
Number
ofNeutrons
A 3 7
B 6 12
C 19 10
D 16 16
E 17 18
F 40 20
Q1 Fill in the blanks
Q1 Answers
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Elements Proton
Number
Nucleon
Number
Number
ofNeutrons
A 3 7 4
B 6 12 6
C 9 19 10
D 16 32 16
E 17 35 18
F 20 40 20
Q1 Answers
Q2 Fill in the blanks
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Elements NumberofNeutron
NucleonNumber Numberofelectrons
ElectronConfiguration
A 5 9
B 8 2.6C 19 2.7
D 14 2.8.3
E 32 16
F 20 40
Q2 Fill in the blanks
Q2 Answers
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Elements NumberofNeutron
NucleonNumber Numberofelectrons
ElectronConfiguration
A 5 9 4 2.2
B 8 16 8 2.6C 10 19 9 2.7
D 14 27 13 2.8.3
E 16 32 16 2.8.6
F 20 40 20 2.8.8.2
Q2 Answers
2 3 ISOTOPES
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2.3 ISOTOPES
What is isotopes?
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Isotopes is just like twins,
same genetic but different of DNA
atoms of the same element withsame number of protons butdifferent number of neutrons
What is isotopes?
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Examples of Isotopes Take a look at Wikipedia isotopes table
Hydrogen :
Graphite :
Oxygen :
1
1
H3
1
H2
1
H
12
6C
14
6C
13
6C
16
8O18
8O17
8O
Isotopes of Hydrogen
http://localhost/var/www/apps/conversion/tmp/scratch_5/Isotope%20table%20(complete)%20-%20Wikipedia,%20the%20free%20encyclopedia.htmhttp://localhost/var/www/apps/conversion/tmp/scratch_5/Isotope%20table%20(complete)%20-%20Wikipedia,%20the%20free%20encyclopedia.htm7/29/2019 chemistry chapter 2 form 4
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Isotopes of Hydrogen
Hydrogen :
1
1
H
2
1
H
3
1
H
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Properties of isotopesOxygenIsotopes
No of proton
No of neutron
No of e-
e- configuration
Valence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 8
No of neutron
No of e-
e
-
configurationValence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 8 8
No of neutron
No of e-
e
-
configurationValence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 8 8 8
No of neutron
No of e-
e
-
configurationValence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16
No of e-
e
-
configurationValence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17
No of e-
e
-
configurationValence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e-
e
-
configurationValence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16
e- configuration
Valence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16
e- configuration
Valence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16 16
e- configuration
Valence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16 16
e- configuration 2.8.6
Valence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16 16
e- configuration 2.8.6 2.8.6
Valence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16 16
e- configuration 2.8.6 2.8.6 2.8.6
Valence e-
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16 16
e- configuration 2.8.6 2.8.6 2.8.6
Valence e- 6
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16 16
e- configuration 2.8.6 2.8.6 2.8.6
Valence e- 6 6
16
8O
18
8O17
8O
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Properties of isotopesOxygenIsotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e- 16 16 16
e- configuration 2.8.6 2.8.6 2.8.6
Valence e- 6 6 6
16
8O
18
8O17
8O
Conclusion:
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Conclusion:
Number of valence electron are same
The chemical properties also same
The physical properties might besame, might be different
Try this out!!!
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Try this out!!!
Q3. Answer the structure questions
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Elements Proton Number Nucleon Number
P 3 7
Q 9 19
R 16 32
S 15 31T 16 33
U 18 40
a ) What means proton number?
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A: The numbers of proton in the nucleus of an atom
b) What means nucleon number?A: The numbers of proton & neutron in the nucleus
of an atom
c) Write the electron arrangement for element Q.
A: 2.7
d) How many valence electrons that element Q has?
A: 7
e) How many electron shells that element Q has?
A: two
f) Which pair of elements are isotopes? Explain.
A R & T
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4018
U
A: R & T.
Because they have same proton number but
different nucleon number
g) Is R&T have same chemical properties? Why?
A: Yes. Because they have same valence electron
h) How many protons, neutrons, and electrons are
there in atom S?
A: 15 protons, 16 neutrons and 15 electrons
i) Write the symbol to represent atom U.A: 40
18U
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