Transcript THE PERIODIC TABLE

THE PERIODIC TABLE
History of the periodic table and
the creation of the modern design
Overview
RECALL:
• The periodic table lists the 110+ elements
• All matter is made up of a different combinations
of elements
• Elements are pure substances and cannot be
broken down into simpler substances
• Compounds are elements formed into molecules.
Elements
• Each element on the
•
table explains the
following information:
Atomic number = # of
protons in the nucleus
of that atom
(notice how the elements increase
in atomic number, 1 is at the
top right and increases as you
move to the right and down the
table)
Elements
Each element on the table explains
the following information:
• The element’s symbol
and name
 Short hand (one or two
letters) and name
• Atomic Mass:
 Mass of average atom of
element
 # of protons + # of neutrons
Elements
Each element on the table explains
the following information:
• Ion Charge:
 The charge that is created when
an element gains or loses
electrons
 An atom that gains an electron
gets a negative charge. Why?
 An atom that loses an electron
gets a positive charge. Why?
 If element has more than one
charge it can form more than one
type of bond.
Grouping the Elements
• Elements are
grouped into three
categories
1. Metals
2. Non-metals
3. Metalloids
-share properties
of both metals
and non-metals
How the table is organized
Horizontally
• Each horizontal row is
called a PERIOD.
• Periods are numbered
1-7 moving down the
table
Vertically
• Each vertical column
is called a FAMILY or
GROUP.
• Elements in the same
family have similar
properties and
characteristics.
• Families are
numbered 1 -18.
Alkali Metals - Group 1
• Alkali Metals
 Include Lithium, Sodium
and Potassium
 Reactive metals that
increase in reactivity as you
move down the table. React
vigorously with water.
 Reactivity
 Soft metals that you can
cut with a knife
 Very low melting points
Alkaline Earth Metals
Group 2
• Less reactive than
•
•
•
Alkali metals
Burn in air if heated
Produce bright flames
and used in fireworks
Will react with water,
but less than alkali
metals.
Halogens - Group 17
• Non-metals and highly
•
•
•
reactive
Fluorine and Chlorine are
gases, Bromine is a liquid
and Iodine is a solid at
room temperature.
Fluorine is most reactive,
iodine is least
Often used as bleaching
agents for cleaning (kills
bacteria)
Noble Gases - Group 18
• Most stable and un•
•
reactive elements
Colourless, odourless
gases at room temp.
Neon and argon used
in light fixture and
glow in distinctive
colours.
Homework
• Chapter 2.2 Review Pg 63 #2,4,5,8,9,1114, 17-21.