The document provides information about the periodic table, including its development and structure. It discusses how elements are arranged in rows and columns called periods and groups. The main groups discussed are the alkali metals, alkaline earth metals, boron family, carbon family, nitrogen family, oxygen family, halogens, noble gases, and transition metals. It also notes the location of metals on the left side and nonmetals on the right, separated by a zigzag line.
2. Organic Chemistry II
Organic chemistry provides the student
with the necessary background to
understand the chemistry of carbon-
containing compounds
Students registering for CHEM 221 must
have a good background in general
chemistry.
4. Modern Periodic Table
A number of scientists
attempted to improve
Mendeleev’s periodic table.
Credit cannot be given to any
single person because a lot of
scientists worked hand in hand
in perfecting this table.
5. Periodic Table
It gives us a lot of information
about an element
It also gives us an idea as to why
an element is grouped together
with other elements or why it is
located at a specific spot in the
Periodic Table.
6. Chemical Symbols
Jons Jakob Berzelius (1779-1848)
- A Swedish chemist, was the first to use
letters or symbols for the elements.
(Note: in some cases, the symbol of an element
is the first letter of its name.
*In many cases, a second letter is added to
the first in order to distinguish between
elements whose names begin with the same
letter. E.g. C stands for carbon and Ca stands
for calcium.
*Some of the symbols are based on the latin
names of the elements.)
7. What is the significance of a
symbol?
A symbol as used in chemistry, is more than
an abbreviation. It tells us three things:
a. The name of the element
b. Atom of the element
c. Atomic mass of the element.
e.g.
Cl means ( a. the element chlorine; b. one
atom of chlorine; c. 35 amu of chlorine)
8. A Periodic Table has columns ( vertical
list) and rows (horizontal list). The
columns are referred to as family or
group while the rows are called periods.
1. How many families are shown in the
periodic table?
2. How many periods are shown in the
periodic table?
10. Families of Elements in the
Modern Periodic Table
How do we describe a Periodic table?
What are the groups and why they are
named as such?
a. The elements are arranged in the order
of increasing atomic numbers from left
to right and from top to bottom.
b. The groups of elements are classified
further into the following main
categories of elements:
11. 1). GROUP IA to VIIA (Main Group or
representative Elements)
a. Group IA elements – Alkali metals bec. these
elements are highly reactive metals
b. Group IIA elements- Alkaline earth metals
(chemically reactive metals)
c. Group IIIA- Boron Family
• boron- has a low electrical conductivity
• Aluminum- most abundant metal of the earth’s
crust. Alum or tawas, one of the compounds of
aluminum.
12. d. Group IVA, the carbon Family (is found
in all living things)
e. Group VA, the nitrogen family (it
dilutes the oxygen in the air and prevents
combustion and respiration taking place
rapidly.)
f. Group VIA, The oxygen Family
( it exists in two allotropic forms)
g. Group VIIA are all nonmetals.
They are known as halogens, meaning salt
former.
13. 2. Group VIIIA or O (Noble or Inert Gases)
-these elements are gases which are highly
stable because of their closed or complete
electronic configuration. They do not form
any compound.
3. Group B Elements (Transition Metals)
-the members of this group are all metals
which include familiar elements like iron and
chromium etc.
14. Two Special Groups
Lanthanoides or Lanthanide
series is composed of elements
with atomic numbers 57 to 71,
Actinoides or Actinide series is
composed of radioactive elements
with atomic numbers 89 to 103.
15. C. Metals are found on the left side of the
periodic table and are shown in blue color
while nonmetals, in orange color, are on the
right side. They are separated by a heavy zigzag
line starting between boron and aluminum
polonium and astatine. They are shown in red
color.
D. The elements along the border line between
he metals and non-metals also show
intermediate properties and are called
metalloids or amphoteric elements.
16. Important Elements in
Environment and Industry
Hydrogen- is the lightest element and is
sometimes used to fly balloons.
Nitrogen- unreactive gas and abundant in the
atmosphere.
Carbon in activated charcoal has an adsorbent
property of attracting and holding materials to
its surface. This makes it a good purifier to
remove color and odor from certain gases and
liquids. It is also used in gas mask to inhale air
that is free from air pollution.
17. Iron, because of its metallic property, it
is widely used in industry.
Copper has a very good conductivity.
It is, therefore, widely used as electric
wirings.
Oxygen supports combustions and is
used in torches for welding.
