•Structured arrangement of elements that help us to explain and
predict physical and chemical properties
•Metals are located on the left side
•Non-metals are located on the right side (exception: H)
•Metalloids are found on either side of the staircase (exception: Al)
Property
Metals
Non-Metals
Example
nickel, Ni
bromine, Br
State
mostly solid
solid, liquid or gas
Lustre
shiny
dull
Malleability
generally malleable
brittle (if solid)
Conductivity
conductors
insulators
Sodium, Na
Carbon, C
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Period: row of elements on the
periodic table
 Indicate the number of shells

Group: columns on the periodic
table with similar properties
 Indicate the number of valence electrons


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Group 1 elements (exception: H);
e.g. Na, Li, K
Highly reactive metals
Like to form ionic compounds with
group 17 non-metals


Group 2 elements e.g. Mg, Ca, Ba
Fairly reactive metals


Group 17 elements e.g. F, Cl, Br
Highly reactive non-metals


Group 18 elements e.g. He, Ne, Ar
Stable, unreactive elements

Recall:
 The first orbit can hold 2 electrons
 The second and third orbits can hold a
maximum of 8 electrons
▪ Atomic number = # of protons
▪ # protons = # electrons (in a neutral atom)
▪ Atomic mass – Atomic Number = # neutrons
• Simplified drawing representing the valence
electrons
• Draw the element’s symbol and surround its 4
sides with dots which represent the valence
electrons
Recall: Group # = # of valence electrons
H
F
Hydrogen
Fluorine