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Elements Notes
Name: ______________________(
) Class: 1 ____ Date: ____________
Elements
An element is a substance which cannot be broken down into two
or more simpler substances by chemical methods.
Elements are the simplest kind of matter.
There are more than 100 elements in the universe.
All discovered elements are listed in the Periodic Table.
The Periodic Table
Every element is represented by a unique symbol of one or two letters. If there are two letters in the
symbol, the 2nd letter must be a small letter!
E.g. CO (____________________________) is not the same as Co (_______________)!
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Every element in the Periodic table is given a unique number called the atomic number. The atomic
number is at the bottom left corner of the element’s box.
Activity - Name the elements!
Symbol
Element
Atomic
Number
Symbol
H
Mg
O
He
N
Ne
C
Cl
Au
Hg
Ag
Na
Cu
Fe
Al
S
Zn
I
Element
Atomic
number
Classifying elements
The periodic table is a very organised system.
Elements have been placed systematically into the Periodic Table according to their properties.
Scientists have classified elements into 2 main groups, the metals and non-metals.
Each vertical column is called a _____________________. Each group’s number is reflected at the
top of the periodic table.
Elements in the same group have similar ________________________ and will undergo the same
type of chemical reactions. Each group has its own unique properties.
Each horizontal row is called a _____________________.
The periods are numbered from the top row down.
Elements in a period from left to right show a gradual change from ________________________ to
________________________.
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Elements to the left of the zig-zag line in the Periodic Table are metals, while those to the right of the
zig-zag line are non-metals.
Metals vs Non-metals
General Properties
Metals
Non-metals
Examples
Appearance
Electrical and heat
conductivity
Melting/boiling point
Ductility (ability to be
drawn into wires) and
malleability (ability to be
flattened into sheets)
Density
Ability to produce sound
when hit
Activity - Without looking at the periodic table, circle the metals in the list!
Silver, Gold, Helium, Neon, Titanium, Hydrogen gas, Platinum,
Nitrogen gas, Chlorine gas
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Uses of some common metals
(Note: The chemical formula of a metal is always just its element symbol.)
Element /
Chemical formula
Uses
Aluminium
(Al)
Zinc
(Zn)
Copper
(Cu)
Magnesium
(Mg)
Mercury (liquid)
(Hg)
Iron
(Fe)
More ACE ideas to think about:
If metals can be easily flattened into sheets and drawn into wires, why are our metal pots and pans
so hard?
What is steel? It cannot be found in the periodic table – so it is not an element!
On the same note, what is brass?
Or bronze?
What is 12K/18K/24K gold? What is the difference between the different types of gold?
All these questions can be answered with one key word – do you know what it is? 
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Uses of some common non-metals
(Note: The chemical formula of a non-metal will usually have a subscript to the right of the symbol.
This number represents the number of atoms in a molecule of the element. For example, Cl2 means
that there are 2 Cl atoms in a molecule of chlorine gas. You will learn more about this in Sec 2 and
Upper Sec Chemistry  However, if you are interested to read up more, go ahead!)
Element /
Chemical formula
Uses
Note: Carbon exists in various forms known as allotropes (what are
allotropes? - possible ACE idea!)
Graphite:
Carbon (solid)
(C)
Diamond:
Charcoal:
Sulfur (solid)
(S8)
Chlorine gas
(Cl2)
Nitrogen gas
(N2)
Iodine (solid)
(I2)
Hydrogen gas
(H2)
Oxygen gas
(O2)
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