I don't actually have a personal identity or preferences. I'm an AI assistant created by Anthropic to be helpful, harmless, and honest.

2. Recall
Complete the following information by using
your periodic table of elements
Atomic number
Symbol
Atomic mass
Number of
protons
Number of
electrons
Number of
neutrons
Argon
Silver
Silicon

3. Recall
Atomic
number
18
Argon
Symbol
Ar
Mass number
40
Number of protons
Number of electrons
Number of neutrons
18
18
22

4. Recall
Atomic
number
47
Silver
Symbol
Ag
Mass number
108
Number of protons
Number of electrons
Number of neutrons
47
47
61

5. Recall
Atomic
number
14
Silicon
Symbol
Si
Mass number
28
Number of protons
Number of electrons
Number of neutrons
14
14
14

6. Learning
Objectives
Melc 19- Use the
periodic table to
predict the
chemical behavior
of an element
Value
Value the importance of the Periodic Table of
elements and explain why there is a need to group
elements in specific arrangements.
Group
Group elements according to similarities in
chemical properties.
Cite
Cite the scientists who made great
contributions to the development of the
Periodic Table of Elements;
Predict
Predict the chemical behavior and properties of
elements using the features of the periodic table
of elements;
Identify Identify groups and series of elements;

7. Which one is comfortable to
stay? The messy or the
organized?
Before After

8. Introduction:
In this lesson you will learn that elements
were arranged in the periodic table in rows
and columns according to increasing atomic
number. This arrangement was based on
properties of elements which were found to
be repeated regularly through the elements
arranged according to increasing atomic
number.

9. Key Questions
How did the
Periodic table
develop?
What information
about elements can
be obtained from
this organized tool?

10. What is a Periodic Table?
 Shows all elements
in the universe
 A tabular organized
display of the
chemical elements,
which arranged by
atomic number and
chemical properties

11. Development of the Periodic
Table
Scientist have always searched for patterns,
regularities and symmetries in nature. It can
be discovered, information and data can be
arranged and organized in ways that will make
it more understandable, meaningful and
useful. An excellent example of this is the
periodic table

12. Johann Dobereiner
 a German chemist
who formed the
triads of elements
with similar
properties
 The elements in a
triad has similar
chemical properties
and orderly physical
properties

13. John Newlands (1864)
John Newlands proposed an
arrangement where elements
were ordered by increasing
atomic mass
Newlands noticed when the
elements were arranged by
increasing atomic mass, their
properties repeated every
eighth element (law of octaves).

14. Lothar Meyer and Dmitri
Mendeleev (1869)
 Meyer and Mendeleev both demonstrated a
connection between atomic mass and elemental
properties.
 Mendeleev is given more credit because he
published his information first.
 Arranged elements in order of increasing atomic
mass into columns with similar properties.
 Mendeleev was able to predict the existence
and properties of undiscovered elements (blank
spaces).

15. Mendeleev’s Periodic
table

16. Henry Moseley (1914)
 An English physicist observed that
the order of the X-ray frequencies
emitted by elements follows the
ordering of the elements by atomic
number.
 Modern Periodic Law- the
properties of elements vary
periodically with atomic number
 Moseley rearranged the table by
increasing atomic number and
resulted in a clear periodic pattern.

17. Moseley’s Periodic table

18. Performance Task 4
 Complete the graphic organizer below by stating the scientists you
learned and their contributions to the development of the periodic
table of elements.
Development
of the Periodic
table of
elements
(name of
Scientist)
Contribution
(name of
Scientist)
Contribution
(name of
Scientist)
Contribution
(name of
Scientist)
Contribution
(name of
Scientist)
Contribution

19. Week 8

20. Modern Periodic table
https://youtu.be/t_f8bB1kf6M- Classification of
elements

21. What is a Periodic Table?
 Shows all elements
in the universe
 A tabular display
of the chemical
elements, which
arranged by atomic
number and
chemical
properties

22. What information would you get
in the periodic table?
6
C
Carbon
12.01
Atomic number
Symbol
Element name
Atomic Mass

23. What information do we get in
the Periodic Table?
Main Groups
1. Alkali Metals
(Group 1)
2. Alkaline Earth
Metals (Group 2)
3. Halogens (Group
17)
4. Noble Gases (Group
18)
5. Transition
elements
Specialized
Series
1. Lanthanide
series
2. Actinide
series
Nature of
Elements
through a
ladder like line
1. Metals
2. Non-metals
3. Metalloids

24. Main Groups and Specialized
groups
Specialized
Group
Main
Groups

25. Nature of Elements through a
ladder like line

26. What other information could
we get in the periodic table?
Period
Group/Family
Trends in the
Periodic Table

27. Vocabulary Words
Periods
 Horizontal row of elements
 Elements are not alike in
properties
 The first element in the
period is active solid, the
last element is always
inactive gas
Families
 Columns of elements
 Elements in each family have
similar but not identical
properties
 Example (Li, Na, K and other
members of the family IA
are all soft and shinny
 Elements in family have the
same number of valence
electrons

28. What are
the
examples of
non-metals?

29. Properties of Metalloids
 Metalloids (metal-like)
have properties of both
metals and non-metals
 They are solids that can
be shiny or dull
 They conduct heat and
electricity better than
non-metals but not as well
as metals
 They are ductile and
malleable

30. Period
 Horizontal row of elements
 Elements are not alike in
properties
 The first element in the
period is active solid, the
last element is always
inactive gas
 Same number of energy
shells

31. Period of the Periodic table

32. Questions?
Which Period do this elements belong?
Element Period
A.Silver
B.Selenium
C.Polonium
D.Sulfur
E.Neon
5 4
6
3 2

33. How many groups are there in
the Periodic table?
There are 18 groups
in the periodic table,
each group has its
unique family name
Alkali metals-
Group 1
Alkaline earth
metals- Group
2
Transition
metals- Group
3-12
Boron family-
Group 13
Carbon
family- Group
14
Nitrogen
family- Group
15
Oxygen
family-
Group-16
Halogens
Group 17
Noble gases-
Group 18

34. What do
you think
are the
basis in
grouping
the
elements?
 Base on their
similarities and
chemical properties,
each group of elements
have the same number
of valence electrons.
 Example (Li, Na, K )
and other members of
the family IA/group 1
are all soft and shinny

35. Families of the Periodic
table

36. Families of the Periodic
table

37. HYDROGEN
The hydrogen square sits atop Family AI, but it is
not a member of that family. Hydrogen is in a class of
its own
It’s a gas at room temperature
It has one proton, one electron and only one
energy level

38. ALKALI METALS
Sodium (Na)
The alkali family is found in the first
column of the periodic table
Atoms of the alkali metals have a
single electron in their outermost
level, in other words, 1 valence
electron
They are shiny, have the consistency
of the day, and are easily cut with a
knife

39. ALKALI METALS
They are the most reactive
metals
They react violently with
water
Alkali metals are never found as
free elements in nature. They are
always bonded with another
element

40. Alkaline Earth
Metals
 They are never found
uncombined in nature
 They have two valence
electrons
 shiny
 silvery-white
 somewhat reactive
metals at standard
temperature and
pressure.

41. Transition Metals
Transition
Elements
include those
elements in
the B/Group
3-12 families

42. Boron Family
The Boron Family is named after the first
element in the family
Atoms in this family have 3 valence electron
Boron is metalloid
Most are metals
This family includes the most abundant metal in
the earth’s crust( aluminum)
Solid at room temperature
Reactive

43. Carbon Family
4 Valence
Electrons
Contains metals( Sn
& Pb) metalloids( Si
& Ge) and non-metal
(C)
Reactive
Properties vary
among elements
Solid at room
temperature
Example: Carbon is in all
living things and even
some nonliving things
like diamonds and fossil
fuels

44. Nitrogen Family
The nitrogen family is named
after the element that makes
up 78% of our atmosphere
This family includes non-
metals, metalloids and metals
All members of the nitrogen
family have five electrons in
their outermost energy level
These elements lose
electrons easily
Ex. Phosphorus, arsenic,
antimony and bismuth

45. Oxygen Family
Atoms of this family
have 6 valence
electrons
Most elements in this
family share electrons
when forming
compounds
Oxygen is the most abundant
element in the earth’s crust. It is
extremely active and combines
with almost all elements.

46. Halogen Family
 The elements in this family
are fluorine, chlorine, bromine,
iodine and astatine
 Halogens have 7 valence
electrons, which explains why
they are the most active non-
metals. They are never found
free in nature
 Halogen atoms only need to
gain 1 electron to fill their
outermost energy level
 They react with alkali metals
to form salts

47. Noble Gases
 Noble gases are colorless gases that are
extremely un-reactive
 One important property of the noble
gases is their inactivity. They are
inactive because their outermost energy
level is full
 Because they do not readily combine with
other elements to form compounds, the
noble gases are called inert
 The family of noble gases includes helium,
neon, argon, krypton, xenon and radon
 All the noble gases are found in small
amounts in the earth’s atmosphere

48. Rare Earth
Metals
 This is
composed of
the
lanthanide
and actinide
series

49. Periodic Trends

50. Why are
some
elements
so
reactive?
Valence electron
determine the
reactivity of some
elements, if a group
of elements has 1
valence electron,
they are highly
reactive.

51. Periodic Trends
 Relates to how easy
it is for an atom to
lose electron
Metallic
Property
Non-Metallic
Property
 Relates to how easy
it is for an atom to
gain an electron

52. During Chemical reaction
Atoms may gain or loose electron
Cation- atom that lose electron
Anion- atom that gains electron

53. Valence Electron
How many valence electron are
there in sodium?

54. Metallic and Non-Metallic
Character

55. To sum up: Let’s complete the table
below
Element Group Family Period Valence
electron
Potassium 1 _____ 4 _____
Silicon ____ Carbon _____ 4
Aluminum 13 _____ _____ 3
Barium ____ _____ 6 2
Chlorine 17 Halogens ____ _____

56. To sum up: Let’s complete the table
below
Element Group Family Period Valence
electron
Potassium 1 Alkali
metal
4 1
Silicon 14 Carbon 3 4
Aluminum 13 Boron 3 3
Barium 2 Alkaline
earth
metal
6 2
Chlorine 17 Halogens 3 7

57. Who are you?
If you have given a
chance to be one of an
element in the periodic
table, what of element
are you and why?