Chemistry Atoms Theories

1. CHAPTER 2CHAPTER 2

2. 2.1 MATTER
Most of the things that
we could see in this world
are MATTER

3. What is matter?
Matter means:
- anything that occupies space &
has mass
- made up of tiny & discrete
particles
- Exist as element @ compoundNext

4. A pure substance which
cannot be broken down into
simpler substance physically
& chemically
Matter

5. Usually made up of
two or more elements
which are chemically
bonded together
Matter

6. • Matter are made up of tiny &
discrete particles
• Size of particles are very
minute ~~ 1x 10-7
cm
3. Consist of atoms, molecules
ions Next

7. Let’s see the particles in
bromine liquid
Particle theory

8. The smallest particle of an element
and not breakable anymore.
Examples:
Atom of hydrogen
atom of magnesium
atom of oxygen
atom of chlorine
H
Mg
Cl
O
Particle theory

9. A group of two @ more atoms,
which might consist of:
one type of element (Element)
@ different types of element
(Compound)

10. Examples of element molecules:
Molecule of hydrogen gas
Molecule of oxygen gas
Molecule of chlorine gas
OO
Cl Cl
H
H

11. Examples of compound molecules:
Molecule of water, H2O
Molecule of ammonia, NH3
Molecule of ethanol, C2H5OH
H
H
O
H
H
H N
O
C C
H
H
H
H
H
H
Particle theory

12. Ions are atoms which have
charge
Positively-charged ion /cation (loss e-
)
Negatively charged ion / anion (gain e-)
+
-

13. 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 electron
O
Cl
-
Gain electronCl
Symbol of element
Examples of ions:

15. • Kinetic means motion (move)
• Kinetic theory states that:
1. Matter consist of particles which
constantly moving

16. 2. particles move in random motion ,
collide with each other

17. • substance is cooled,
- particles lose kinetic energy
- move slower
B. substance is heated,
- particles gain kinetic energy
- move faster

18. Heat energy makes particles
move faster!!!

19. Experiment which supports
the kinetic theory:
Investigating the diffusion of
particles in a
solid, liquid and gas

20. What is diffusion ?What is diffusion ?
How diffusion supportsHow diffusion supports thethe
kinetic theorykinetic theory ??

21. Diffusion happens anyway that
different concentration
of particles

22. Is the rate of diffusion different
in solid, liquid,
and gas state?
Let’s get an experiment
to check it out!!!

23. Diffusion in Solid (membrane)

24. Diffusion in Liquid ( )

25. Diffusion in Gas (air)

26. Diffusion affected by Density

29. 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

31. The Physical States of Matter
Solid
Liquid
Gas

32. The Arrangement of Particles

33. The Shape & Volume of Particles

34. The Movement & Energy Content
of Particles

35. The Attraction Force
between Particles

36. The Physical Changes of Matter
Freezing
GasLiquid
Solid
Melting
Sublimatio
n
Boiling
Condensati
on
Sublimatio
n

37. Determine the
Melting Point of Naphthalene
Melting point –
the temperature
which a solid
becomes liquid

38. Diagram of heating naphthalene
Q1-Q4 Q5-Q7
Solid naphthalene
Water

39. Heating curve of naphthalene
A
C
B
D
Temperature / ˚C
Time / minute
79˚C
Q1-Q4 Q5-Q7

41. What is the Melting point?
A: 79˚C
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

42. Why the curve of heating has no change at B-C?
A: because the heat energy absorbed by
naphthalene molecules to overcome the forces of
attraction to becomes liquid
Why solid naphthalene heated in water ?
A: to ensure a uniform heating
If the melting point of Substance X is 123˚C, can
we still use water as medium? Why?
A: No. Because its melting point is higher than
the boiling point of water. We can use oil bath to
replace water. graph apparatusPhysical changes

43. Determine the
Freezing Point of Naphthalene
Freezing point – the
temperature which a solution
becomes solid

44. Cooling curve of naphthalene
Q1-Q4 Q5-Q7
79˚C
E
Temperature / ˚C
G
H
Time / minute
F

45. Is the freezing point same with the Melting point?
A: Yes, both are 79˚C
What is the physical state change in this experiment?
A: Liquid naphthalene changes to solid
Where is the point that
freezing process started?
A: F
Where is the point that
freezing process ended?
A: G

46. 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 to
surroundings
Why liquid naphthalene in the boiling tube is cooled
inside a conical flask?
A: to ensure a uniform cooling

47. Different solution has different
boiling point & freezing point

48. Diagram of cooling naphthalene
Q1-Q4 Q5-Q7
Liquid naphthalene
Empty conical flask

49. 2.2 ATOMIC STRUCTURE

50. The Historical Development Of
Atomic Models
• John Dalton – imagine atom as a
indivisible tiny ball
• J.J. Thomson – discovered electrons
• Ernest Rutherford – discovered proton,
mass of atom concentrated in nucleus
• Neils Bohr – proposed the electrons
move in shells around the nucleus
• James Chadwick – proved the existence
of neutrons

51. Subatomic Particle In An Atom

52. Subatomic Particle In An Atom
Proton
Neutron
Electron

53. Subatomic Particle In An Atom
Proton Electron
Neutron
Nucleus
of atom Electron
shells

54. Subatomic Particle In An Atom

55. Subatomic Particle In An Atom

56. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol
Electric Charge
Relative Mass
Location

57. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p
Electric Charge
Relative Mass
Location

58. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n
Electric Charge
Relative Mass
Location

59. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge
Relative Mass
Location

60. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1
Relative Mass
Location

61. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0
Relative Mass
Location

62. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass
Location

63. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1
Location

64. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1
Location

65. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 ≈ 0
Location

66. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 ≈ 0
Location in the
nucleus
atom

67. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 ≈ 0
Location in the
nucleus
atom
in the
nucleus
atom

68. Subatomic Particle In An Atom
PROPERTIES PROTON NEUTRON ELECTRON
Symbol p n e-
Electric Charge +1 0 -1
Relative Mass 1 1 1/1240 ≈ 0
Location in the
nucleus
atom
in the
nucleus
atom
Electron
shells which
around the
nucleus atom

70. 40
20
Ca
Nucleon 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

71. Electron Configuration
Also known as electron arrangement
How electrons fill into the shells?

72. 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

73. 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

74. Fluorine F
Proton number 9
2 . 7
Neon Ne
Proton number 10
2 . 8
Sodium Na
Proton number 11
2 . 8 . 1
Magnesium Mg
Proton number 12
2 . 8 . 2

75. Aluminium Al
Proton number 13
2 . 8 . 3
Silicon Si
Proton number 14
2 . 8 . 4
Phosphorus P
Proton number 15
2 . 8 . 5
Sulphur S
Proton number 16
2 . 8 . 6

76. 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

77. Conclusion:Conclusion:
1st Shell: max1st Shell: max 22 e-e-
2nd Shell: max2nd Shell: max 88 e-e-
3rd Shell: max3rd Shell: max 88 e-e-

78. ARRANGEMENT OF SHELLS IN AN ATOM
NUCLEUS
2 ELECTRONS
8 ELECTRONS
8 ELECTRONS
18 ELECTRONS
1
2
3
4

79. Electron arrangement in the
carbon atom
C
12
6
 proton number = 6
number of protons = 6
number of electrons = 6
2 . 4
= electron
nucleus
Number of valence
electrons = 4

80. 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

82. Try to draw out the
electron
arrangement in
shells

83. Draw & state the electron arrangement of
the elements below
X
15
7
Y
24
12
Z
39
19

84. Let us learn some
chemical words !!

85. • Proton number (p) –
number of protons in the nucleus of atom
• Nucleon number (p+n)–
total number of protons and neutrons in
the nucleus of atom
3. Valence electron –
the electrons in the outermost shell
4. Electron configuration –
arrangement of electron

86. Repeat them !!
Proton number
number of protons in the nucleus of atom
Nucleon number
total number of protons and nucleons
in the nucleus of atom
Valence electron
the electrons in the outermost shell
Electron configuration –
arrangement of electron

87. Try this out!!!

88. Elements Proton
Number
Nucleon
Number
Number
of
Neutrons
A 3 7
B 6 12
C 19 10
D 16 16
E 17 18
F 40 20
Q1 Fill in the blanks

89. Elements Proton
Number
Nucleon
Number
Number
of
Neutrons
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

90. Elements Number
of
Neutron
Nucleon
Number
Number
of
electrons
Electron
Configuration
A 5 9
B 8 2.6
C 19 2.7
D 14 2.8.3
E 32 16
F 20 40
Q2 Fill in the blanks

91. Elements Number
of
Neutron
Nucleon
Number
Number
of
electrons
Electron
Configuration
A 5 9 4 2.2
B 8 16 8 2.6
C 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

92. 2.3 ISOTOPES

93. • Isotopes is just like twins,
same genetic but different of DNA
• atoms of the same element with
same number of protons but
different number of neutrons
What is isotopes?

94. Examples of Isotopes
• Take a look at Wikipedia isotopes table
• Hydrogen :
• Graphite :
• Oxygen :
1
1
H
3
1
H
2
1
H
12
6
C
14
6
C
13
6
C
16
8
O
18
8
O17
8
O

95. Isotopes of Hydrogen
Hydrogen :
1
1
H
2
1
H
3
1
H

96. Properties of isotopes
Oxygen
Isotopes
No of proton
No of neutron
No of e-
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

97. Properties of isotopes
Oxygen
Isotopes
No of proton 8
No of neutron
No of e-
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

98. Properties of isotopes
Oxygen
Isotopes
No of proton 8 8
No of neutron
No of e-
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

99. Properties of isotopes
Oxygen
Isotopes
No of proton 8 8 8
No of neutron
No of e-
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

100. Properties of isotopes
Oxygen
Isotopes
No of proton 16 16 16
No of neutron 16
No of e-
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

101. Properties of isotopes
Oxygen
Isotopes
No of proton 16 16 16
No of neutron 16 17
No of e-
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

102. Properties of isotopes
Oxygen
Isotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e-
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

103. Properties of isotopes
Oxygen
Isotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e-
16
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

104. Properties of isotopes
Oxygen
Isotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e-
16 16
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

105. Properties of isotopes
Oxygen
Isotopes
No of proton 16 16 16
No of neutron 16 17 18
No of e-
16 16 16
e-
configuration
Valence e-
16
8
O
18
8
O17
8
O

106. Properties of isotopes
Oxygen
Isotopes
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
8
O
18
8
O17
8
O

107. Properties of isotopes
Oxygen
Isotopes
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
8
O
18
8
O17
8
O

108. Properties of isotopes
Oxygen
Isotopes
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
8
O
18
8
O17
8
O

109. Properties of isotopes
Oxygen
Isotopes
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
8
O
18
8
O17
8
O

110. Properties of isotopes
Oxygen
Isotopes
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
8
O
18
8
O17
8
O

111. Properties of isotopes
Oxygen
Isotopes
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
8
O
18
8
O17
8
O

112. Conclusion:
• Number of valence electron are same
• The chemical properties also same
• The physical properties might be
same, might be different

113. Try this out!!!

114. Elements Proton Number Nucleon Number
P 3 7
Q 9 19
R 16 32
S 15 31
T 16 33
U 18 40
Q3. Answer the structure questions

115. a ) What means proton number?
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

116. 40
18
U
f) Which pair of elements are isotopes? Explain.
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
• 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
18
U