The Periodic Table
Assignment
• Read
– Chapter 1, section 6
– Chapter 3, section 4
– Chapter 3, section 5
The Periodic Table
•
Periodic means occurring or
appearing at regular intervals
•
The Periodic table is designed so
that elements with similar
characteristics occur or appear at
regular intervals
The Periodic Table
•
The table can be divided in many
ways
•
Method 1
– Metals (brown)
– Nonmetal (purple)
– Metalloids or Semi-metals (green)
The Periodic Table
• Metals
–
–
–
–
–
–
Most are solid at room temperature (except mercury, Hg)
Usually are shiny solids when freshly cut
Good conductors of heat and electricity
Malleable (meaning can be flattened into a sheet)
Ductile (meaning can be drawn into a wire)
Most have high melting points and boiling points
The Periodic Table
• Nonmetals
– 11 are gases, 5 are brittle solids, and 1 is a liquid at room
temperature
– Poor conductors of heat and electricity
– Most have low melting points and boiling points
• Metalloids or Semi-metals
– The seven elements that separate the metals and nonmetals
– The metalloids tend to have properties of both metals and
nonmetals
• Ex: Silicon
– Metal-like in that it is a shiny solid
– Nonmetal-like in that it is a brittle solid
– Conductivity lies between that of a metal and non-metal
The Periodic Table
• Method 3
– Group
– Period
The Periodic Table
•
Groups
– Indicated by the number at the top
of each column
– All elements within a group have
similar characteristics or
properties
The Periodic Table
•
Group 1 – Alkali metals
– Soft, shiny metals
– Low melting points compared to
other metals
– Most reactive of the metals that
are not radioactive
– When added to water they form a
highly alkaline (basic) solution –
hence the name alkali metals
The Periodic Table
•
Group 2 – Alkaline Earth Metals
– Shiny solids
– Less reactive than the Alkali
metals
– Higher melting points than the
Alkali metals
The Periodic Table
•
Group 17 – Halogens
–
–
–
–
All are gases except Bromine
Colorful, corrosive nonmetals
Most reactive of all the nonmetals
The group name halogen comes
from the greek word hals,
meaning salt, because the
halogens are only found in nature
in combination with other
elements typically forming a salt.
The Periodic Table
•
Group 18 – Noble Gases
– Named noble because they lack
reactivity.
The Periodic Table
•
Period
– Indicated by the number to the left
of the row in which the element
resides
– We will discuss the importance to
the period # in chapter 3.
The Periodic Table
•
Method 2
– Main Group elements (yellow)
– Transition Metal elements
(orange)
– Inner Transition Metal elements
(blue)
• Are not given group #’s.
• To determine which period they
are members of look at the
elemental numbers (atomic #)
given at the top of each box.
(Expanded version on next slide)
• Elements 58-71 are called the
Lanthanide series because they
follow element #57, Lanthanum
• Elements 90-103 are called the
Actinide series because they
follow element #89, Actinium
•
The divisions in method 2 will be
discussed at length in Chapter 3
The Periodic Table