The history of the periodic table's development, the arrangement of the elements, and the reactivity of each group of elements will all be covered in this lecture.

1. The Periodic Table of
Elements
By: Group 2 Periodic table

2. What is the Periodic Table of Elements?
The periodic table is a tabular representation of all
the chemical elements, arranged in order of their
atomic number, electron configurations, and
chemical properties. The table is divided into rows
(periods) and columns (groups) based on the
elements' electronic structure and chemical
behavior.

3. What is the Periodic Table of Elements?
The elements in each row have the same number of
electron shells, while the elements in each column
have similar chemical properties due to their
electron configuration.

4. What is the Periodic Table of Elements?
The periodic table includes all known elements, from
Hydrogen (atomic number 1) to Ununoctium (atomic
number 118). It is an essential tool for understanding
the properties and behavior of the elements and is
widely used in chemistry, physics, and other
sciences

5. Development of the Periodic Table of Elements
The periodic table is one of the most
important tools in chemistry, which
arranges all the known elements
according to their atomic number and
properties. The credit for creating the
periodic table goes to Dmitri
Mendeleev, a Russian chemist.
• Mendeleev developed the periodic table in
1869.

6. Development of the Periodic Table of Elements
•The periodic table is a tabular arrangement of
chemical elements based on their chemical
properties and atomic structure. The development
of the periodic table began in the early 19th
century with the work of scientists such as
Johann Wolfgang Döbereiner, John Newlands,
and Julius Lothar Meyer, but it was Dmitri
Mendeleev who is credited with the modern form
of the periodic table.

7. Development of the Periodic Table of Elements
•In 1817, Johann Dobereiner
discovered that certain groups of
elements had similar properties and
suggested that elements could be
grouped into triads, where the middle
element had properties that were an
average of the other two.

8. Development of the Periodic Table of Elements
•In 1864, John Newlands
proposed the Law of Octaves,
where he observed that every
eighth element had similar
properties. However, his work
was not widely accepted at the
time.

9. Development of the Periodic Table of Elements
•In 1869, Meyer independently
published a table of elements
organized by valence, the number
of bonds an atom can form with
other atoms. His table included 28
elements, and he noticed that the
properties of elements varied
periodically with their atomic
weight.
valence
: the degree of combining power of an element as shown by the number ofatomic
weights of a monovalent element (such as hydrogen) with which the atomic weight
of the element will combine or forwhich it can be substituted or with which it can
be compared

10. Development of the Periodic Table of Elements
•The breakthrough in the
development of the periodic table
came in 1869 when Dmitri
Mendeleev proposed a periodic
table based on the recurring
properties of elements.

11. Development of the Periodic Table of Elements
•He arranged the elements in
order of increasing atomic mass
and noticed that the properties of
the elements repeated
periodically.

12. Development of the Periodic Table of Elements
•Mendeleev left gaps in his table
for elements that were yet to be
discovered and predicted their
properties based on their
position in the table.

13. Development of the Periodic Table of Elements
•The discovery of the proton in 1911 by Ernest
Rutherford provided a better understanding of the
structure of the atom, and the development of
quantum mechanics in the early 20th century led
to the modern understanding of the electronic
structure of the elements.

14. Development of the Periodic Table of Elements
•In 1913, Henry Moseley
developed a method for
measuring the atomic
number of elements,
which allowed for the
rearrangement of the
periodic table based on
atomic number rather
than atomic mass.

15. Development of the Periodic Table of Elements
• This new
arrangement
provided a better
understanding of the
periodicity of the
elements and their
electronic structure.

16. Development of the Periodic Table of Elements
•Today, the periodic table is a
fundamental tool in chemistry, and it
continues to be updated and refined as
new elements are discovered and their
properties are studied.
•

17. Arrangement of the periodical table
•Metals
➡Metals are a group of elements located on the
left-hand side of the periodic table. They are
characterized by their ability to conduct heat and
electricity, as well as their tendency to form positive
ions.

18. Arrangement of the periodical table
•Metals
➡Metals are generally malleable (able to be
hammered into thin sheets) and ductile (able to be
drawn into thin wires), and have a shiny, reflective
surface when polished.

19. Arrangement of the periodical table
▪Metals
➡Left to side of the periodical table(Except
Hydrogen).
➡ High Electrical Conductivity, high luster, ductile,
malleable.

20. Arrangement of the periodical table
▪Alkali Metal
➡ Group 1 (1A).
▪Alkaline earth metals
➡ Group 2 (2A).
▪Transition metals
➡Group B
➡Lanthanide
➡Actinide series.

22. Arrangement of the periodical table
• Nonmetals
➡Nonmetals are a group of chemical elements
found on the right side of the periodic table. They are
characterized by their lack of metallic properties
such as luster, ductility, and conductivity

23. Arrangement of the periodical table
• Nonmetals
➡Nonmetals are typically gases or brittle solids
at room temperature and have low melting and
boiling points.

24. Arrangement of the periodical table
• Nonmetals
➡Some common nonmetals include hydrogen,
carbon, nitrogen, oxygen, fluorine, and chlorine.

25. Arrangement of the periodical table
• Non-Metals
➡ Right side of the periodic table.
➡ Poor conductions and
non-lustrous.
Halogens
➡Group 17 (7A)
Noble Gasses
➡ Group 1

26. Arrangement of the periodical table
•Mettaloids
In the periodic table, the metalloids are a group
of elements that have properties of both metals and
nonmetals. They are located along the diagonal line
that separates the metals from the nonmetals, also
known as the "staircase" or "zigzag" line.

27. Arrangement of the periodical table
•Mettaloids
They can conduct electricity like metals, but not
as well as typical metals. They can also act as
semiconductors, meaning they can both conduct
and insulate electricity depending on the conditions.

28. Arrangement of the periodical table
•Mettaloids
➡Between Non metals and Metals..
➡Properties intermediate between metals
and non-metals.

30. What is the importance of arranging elements the way they are
arranged in the modern periodic table?
•The importance of arranging elements in this
way lies in the fact that it provides a framework
for organizing and understanding the behavior
of elements and their compounds.

31. Reactivity of Elements
•The reactivity of the elements on the periodic
table can be categorized into several groups

32. Reactivity of Elements
•Alkali Metals (Group 1)
The alkali metals are highly reactive due to
their low ionization energies, meaning they
can easily lose their outermost electron to
form a positive ion. They react vigorously
with water to produce hydrogen gas and an
alkali metal hydroxide

33. Reactivity of Elements
•Alkali Metals (Group 1)
This group includes lithium (Li), sodium (Na),
potassium (K), rubidium (Rb), cesium (Cs), and
francium (Fr).

34. Potassium(K) Sodium(Na) Lithium(Li)

35. Reactivity of Elements
•Alkaline Earth Metals (Group 2)
The alkaline earth metals are also highly
reactive, but less so than the alkali metals. They
also have low ionization energies, but require
more energy to lose their outmost two
electrons. They react with water to produce
hydrogen gas and an alkaline earth metal
hydroxide

36. Reactivity of Elements
•Alkaline Earth Metals (Group 2)
This group includes beryllium (Be), magnesium
(Mg), calcium (Ca), strontium (Sr), barium (Ba),
and radium (Ra).

37. Magnesium(Mg) Calcium(Ca) Barium(Ba)

38. Reactivity of Elements
•Halogens (Group 17)
The halogens are highly reactive nonmetals
that have high electron affinites, meaning
they can easily gain an electron to form a
negative ion. They react vigorously with alkali
metals to produce ionic salts.

39. Reactivity of Elements
•Halogens (Group 17)
This group includes fluorine (F), chlorine (Cl),
bromine (Br), iodine (I), and astatine (At).

40. Bromine (Br) Chlorine (Cl) Flourine (F)

41. Reactivity of Elements
•Nobel Gases (Group 18)
The noble gases are generally unreactive
because they have full valence shells,
making them stable and unlikely to form
chemical bonds.

42. Reactivity of Elements
•Nobel Gases (Group 18)
They include helium (He), neon (Ne), argon
(Ar), krypton (Kr), xenon (Xe), and radon
(Rn)..

43. Neon (Ne) Helium(He) Xenon(Xe)

44. Reactivity of Elements
•Transition Metals (Group 3 - 12)
The transition metals are generally less
reactive than the alkali and alkaline earth
metals, but their reactivity varies depending on
the specific element and its oxidation state.
They can participate in redox reactions and can
form a variety of different compounds.

45. Reactivity of Elements
•Transition Metals (Group 3 - 12)
These metals include well-known
elements such as iron (Fe), copper (Cu), zinc
(Zn), nickel (Ni), gold (Au), and silver (Ag),
among others.

46. Iron (Fe) Nickel (Ni) Silver (Ag)

47. Reactivity of Elements
Overall, the reactivity of an element is largely
determined by its electron configuration, with
the elements having incomplete outermost
electron shells being more likely to react in
order to achieve a stable electron
configuration.

48. Conclusion
The Periodic Table is a visual representation
of all known chemical elements, organized by
their respective atomic numbers and similar
chemical properties. It is concluded with the
placement of the most recently discovered
elements, which are assigned atomic numbers
based on their number of protons.

49. Conclusion
While new elements may be discovered in the
future, the current periodic table serves as a
comprehensive guide for understanding and
studying the properties and behaviors of
various chemical elements.

50. THE END