Development of Periodic Table Trends in the Periodic Table

2. • This idea "vis tellurique" or telluric spiral because the
element tellurium came in the middle.
• It was also somewhat appropriate coming from a geologist
as the element tellurium is named after the Earth.
• He plotted the atomic weights on the outside of a cylinder
such that one complete turn corresponded to an atomic
weight increase of 16.

3. • He pointed out that every eighth element in this grouping
shared a resemblance and suggested an analogy with the
intervals of the musical scale.
• He arranged all the elements known at the time into a
table in order of relative atomic mass.
• He found that each element was similar to the element
eight places further on. For example, starting at Li, Be is
the second element, B is the third and Na is the eighth
element.

4. • He classified some elements into groups of three, which
he called triads.
• The elements in a triad had similar chemical properties
and orderly physical properties.

5. • He published a table of the elements organized by
increasing atomic mass.

6. • In 1913, through his work with X-rays, he determined the
actual nuclear charge (atomic number) of the elements*.
• He rearranged the elements in order of increasing atomic
number.

7. • Recall that the blocks of the periodic table are arranged in to LEFT TO RIGHT
ROWS called a PERIOD/SERIES and UP AND DOWN COLUMNS called a
FAMILY/GROUP.

8. • Each square on the periodic table is known as an ELEMENT KEY and provides
the basic information about each element:

9. • CHEMICAL SYMBOL – a one or two letter abbreviation for the name of an
element.

10. VALENCE ELECTRONS
• One of the most important thing about an atom is the number of VALENCE
ELECTRONS it has.
• Valence Electrons are those electrons found on the outside edge of the
atom, farthest away from the nucleus.

11. • Look at the GROUP NUMBER the element is in.
• Remember the GROUP NUMBER is the numbers 1 to 18 across the tops of the vertical
columns.
• IGNORE the TRANSITION ELEMENTS (groups 3-12) for now.
• ONLY LOOK AT GROUPS 1, 2, 13, 14, 15, 16, 17 and 18.
VALENCE ELECTRONS

12. ACTIVITY 10: FIND THE ELEMENT – use the period/series and family/group information given in each
statement to find the element referred to on the Periodic Table.
a. Period 3 Group 15 ______________________ b. Period 6 Group 12 ________________________
c. Period 2 Group 17 ______________________ d. Period 3 Group 2 _________________________
e. Period 7 Group 11 ______________________ f. Period 4 Group 16 ________________________
g. Period 1 Group 18 _______________________ h. Period 3 Group 13 ________________________
i. Period 5 Group 4 ________________________ j. Period 4 Group 2 __________________________
k. Period 6 Group 14 ______________________ l. Period 4 Group 16 _________________________
m. Period 3 Group 14 ______________________ n. Period 6 Group 11 ________________________

14. ACTIVITY 11: HOW MANY VALENCE ELECTRONS – use the
position of each element on the Periodic Table to determine how many
Ve- each element has.
o. Hydrogen ______
p. Iodine ________
q. Calcium ___________
r. Oxygen _____________
s. Boron _________
t. Magnesium ____
u. Francium _________
v. Tin ___________
w. Carbon ________ x. Xenon _________ y. Sulfur _____________
z. Potassium __________

15. ACTIVITY 12: Give the name of the element that is named after
the following:
a. Scientist
b. Countries
c. Latin names
d. Planets
e. Gods(Greeks/ Norse)

16. Alkali Metals
• The alkali metals, found in group 1 of the periodic table
• very reactive metals that do not occur freely in nature.
• These metals have only one electron in their outer shell
• the alkali metals are malleable, ductile, and are good conductors of heat and
electricity. The alkali metals are softer than most other metals. Cesium and
francium are the most reactive elements in this group. Alkali metals can
explode if they are exposed to water.

17. Alkaline Earth Metals
• The alkaline earth elements are metallic elements found in the second group of
the periodic table.
• All alkaline earth elements have an oxidation number of +2, making them very
reactive.
• Because of their reactivity, the alkaline metals are not found free in nature.

18. Transition Metals
• As with all metals, the transition elements are both ductile and malleable, and
conduct electricity and heat.
• The interesting thing about transition metals is that their valence electrons, or
the electrons they use to combine with other elements, are present in more than
one shell.
• There are three noteworthy elements in the transition metals family. These
elements are iron, cobalt, and nickel, and they are the only elements known to
produce a magnetic field.

19. Other Metals
• these elements are ductile and malleable, they are not the same as the transition
elements.
• All of these elements are solid, have a relatively high density, and are opaque.
They have oxidation numbers of +3, ±4, and -3.

20. Metaloids
• Metalloids have properties of both metals and non-metals.
• Some of the metalloids, such as silicon and germanium, are semi-conductors.
• This means that they can carry an electrical charge under special conditions.

21. Non- Metals
• Non-metals are not able to conduct electricity or heat very well.
• As opposed to metals, non-metallic elements are very brittle, and cannot be
rolled into wires or pounded into sheets.
• The non-metals have no metallic luster, and do not reflect light. They have
oxidation numbers of ±4, -3, and -2.

22. Halogens
• The term "halogen" means "salt-former" and compounds containing halogens
are called "salts".
• All halogens have 7 electrons in their outer shells, giving them an oxidation
number of -1. The halogens exist, at room temperature, in all three states of
matter:

23. Noble Gases
• These elements were considered to be inert gases until the 1960's, because their
oxidation number of 0 prevents the noble gases from forming compounds
readily.
• All noble gases have the maximum number of electrons possible in their outer
shell (2 for Helium, 8 for all others), making them stable.

24. Rare Earth Metals
• One element of the lanthanide series and most of the elements in the actinide
series are called trans-uranium, which means synthetic or man-made.
• All of the rare earth metals are found in group 3 of the periodic table, and the
6th and 7th periods.
• The Rare Earth Elements are made up of two series of elements, the
Lanthanide and Actinide Series.

25. • Increases going up periodic table because there is one fewer
energy level of electrons that will separate the outer electrons
from the nucleus
• Increases going right across periodic table because the nucleus
gains protons and the atom has the same number of energy levels
as you move across a period

26. • Increases going down periodic table because there is an extra
energy level of electrons that will shield the outer electrons
from the nucleus
• Increases slightly going left on periodic table because the
nucleus loses protons and the atom has the same number of
energy levels as you move across a period

27. • Increases going down because there are more energy levels of
electrons and therefore more shielding
• Increases going left because as you move across a period
right-to-left, an atom loses a positively charged proton and
therefore its electrons become slightly less tight and compact

28. • Increases for anions (-) because they gain an electron, which
leads to more shielding
• Decreases for cations (+) because they lose an electron, which
means less shielding

29. • Increases going right because there are more protons in the
nucleus pulling in electrons, so it requires more energy to
remove an outer electron
• Increases going up because there are fewer energy levels and
less shielding, so the outer electrons are more tightly held by
the nucleus

30. • Increases going left because metals are on the left side of the
periodic table and they have fewer protons in their nucleus
that are holding in the atom’s electrons
• Increases going down because there is more shielding, so
outer electrons are easier to lose

31. • Increases going right because non-metals are on the right
side of the periodic table and they have more protons in their
nucleus that attract outer electrons
• Increases going up because there are less electron energy
levels and therefore a greater attraction to the nucleus for
electrons

32. • Increases going right because there are more protons in the
nucleus attracting outer electrons
• Increases going up because there are fewer energy levels of
electrons shielding/repelling new outer electrons

33. ACTIVITY 13: . Directions: Use your notes to answer the following questions. Do NOT
OPEN YOUR PERIODIC TABLE refer to the presentation
1. Rank the following elements by increasing atomic radius: carbon,
aluminum, oxygen, potassium.
2. Rank the following elements by increasing electronegativity: sulfur,
oxygen, neon, aluminum.
3. Why does fluorine have a higher ionization energy than iodine?
4. Why do elements in the same family generally have similar
properties?
5. Indicate whether the following properties increase or decrease from
left to right across the periodic table.
a. atomic radius (excluding noble gases)
b. first ionization energy
c. electronegativity

34. ACTIVITY 13: . Directions: Use your notes to answer the following questions. Do NOT
OPEN YOUR PERIODIC TABLE refer to the presentation
6. What trend in atomic radius occurs across the periodic table? What causes this trend?
7. What trend in ionization energy occurs across a period on the periodic table? What causes this
trend?
8. Circle the atom in each pair that has the largest radius.
a) Al or B
b) Na or Al
c) S or O
d) O or F
e) Br or Cl
f) Mg or Ca
g) Na or Na+1
h) K+1 or Mg+2
i) O or O-2
j) Cl-1 or Br-1

35. ACTIVITY 13: . Directions: Use your notes to answer the following questions. Do NOT
OPEN YOUR PERIODIC TABLE refer to the presentation
9. Circle the atom in each pair that has the greater ionization energy.
a. Li or Be
b. Ca or Ba
c. Na or K
d. P or Ar
e. Cl or Si
f. Li or K
10. Circle the atom in each pair that has the greater electronegativity.
a. Ca or Ga
b. Br or As
c. Li or O
d. Ba or Sr
e. Cl or S
f. O or S

36. I HOPE THIS PRESENTATION WILL
HELP YOU!!!