Transcript Reading the Periodic Table

Introduction to Matter:
Chapter 5:
The Periodic Table
Revised by:
Mrs. Estevez
6 th Grade Science
Reading the Periodic Table
Who arranged the elements?
• Dmitri Mendeleev- Russian Chemist- 1869
• Arranged in order of increasing atomic
mass.
• Periodic- describes something that occurs
or repeats at regular intervals.
• Periodic Law- the law that states that
repeating chemical and physical properties
of elements change periodically with the
atomic numbers of the elements.
Columns
• The vertical (up and
down) columns of the
periodic table (there are
18) are called groups or
families.
• Elements in the same
group or family have
similar chemical and
physical properties.
Rows
• The horizontal rows of the periodic table are
called periods.
• Elements in a period are not alike in
properties.
• The first element in a period is usually an
active solid, and the last element in a period
is always an inactive gas.
Rows
• Atomic number (number of protons)
increases from left to right across a period.
• Atomic mass (number of protons and
neutrons) increases from left to right
across a period.
• Metals are on the left
• Non-metals are on the right
What are the families?
What are metals, non-metals, and
metalloids?
• Metals:
– Tend to be shiny, most are ductile and/or
malleable, good conductors of heat and
electrical current.
• Non-Metals:
– Not malleable or ductile, not shiny, poor
conductors of heat and electrical current.
• Metalloids: (also called semiconductors)
– Properties of both metals and non-metals.
NON-METALS
•not able to conduct electricity or heat very well
•very brittle, and cannot be rolled into wires or pounded into
sheets
•exist in two of the three states of matter at room temperature:
gases (such as oxygen) and solids (such as carbon).
•have no metallic luster, and do not reflect light.
METALLOIDS
•have properties of both metals and nonmetals
•some of the metalloids, such as silicon and
germanium, are semi-conductors. This
means that they can carry an electrical
charge under special conditions. This
property makes metalloids useful in
computers and calculators
ALKALI METALS
Group 1
•very reactive metals because they only have 1
electron in their outer shell
•do not occur freely in nature (combine with other
elements)
•malleable, ductile, good conductors of heat and
electricity.
•softer than most other metals
•can explode if they are exposed to water
ALKLINE EARTH
METALS
Group 2
•metals
•very reactive
•not found free in nature
TRANSITION
METALS
Groups 3-18
•ductile and malleable, and
conduct electricity and heat
•iron, cobalt, and nickel, are
the only elements known to
produce a magnetic field.
RARE EARTH
ELEMENTS
•Top Row: Lanthanides: shiny, reactive metals.
•Bottom Row: Actinides: radioactive (unstable), most are
made in laboratories.
Boron Group
Group 13
•Reactive
•Solids at room temperature
•Boron- metalloid
Carbon Group
Group 14
- Contains
1 non-metal, 2 metalloids, and 3
metals.
- Reactivity varies
- solids at room temperature
-
Nitrogen Group
Group 15
-Contains 2 metals, 2 non-metals, and 2 metalloids
-Reactivity varies
-Solid at room temperature, except for Nitrogen
(it’s a gas)
Oxygen Group
Group 16
-3 non-metals, 1 metalloid, 1 metal
-reactive
-All except oxygen (gas) are solid at room
temperature
HALOGENS
Group 17
•"halogen" means "salt-former" and compounds
containing halogens are called "salts"
•Reactive non-metals (only need 1 extra
electron to complete outer shell)
•exist in all three states of matter:
-Solid- Iodine, Astatine
•Liquid- Bromine
•Gas- Fluorine, Chlorine
NOBLE GASES
Group 18
•Unreactive non-metals (their outer
shell is full)
•Colorless, odorless gasses at
room temperature
Hydrogen:
In a group of
its own…
-Reactive
-Colorless, odorless gas at room temperature
-Low density
-Explosive reactions with oxygen