What is Chemistry?
SIMPLY PUT, IT’S THE STUDY OF THE COMPOSITION, PROPERTIES AND
BEHAVIOUR OF MATTER
Matter: Properties and Changes
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Matter is anything that has mass and takes up space.(e.g. your desk)
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Matter is described by its features or Properties.
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Physical Properties describe how matter appears or anything that
can be observed without forming a new substance. (e.g. colour)
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Chemical Properties describes the characteristics of how matter
reacts, or fails to react, making a new substance. (e.g. flammable)
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A Physical Change occurs when no new substance is formed. (e.g.
ice melting / water freezing)
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A Chemical Change on the other hand, produces a new substance
(e.g. sodium chloride, table salt)
The Classification of Matter
Mixtures and Pure Substances
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A Pure Substance is matter made solely of one kind of material.
(e.g. distilled water)
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A Mixture is made of more than one pure substance. (e.g.
toothpaste)

Heterogenoeus or Mechanical Mixtures are formed by two or more
visible parts. (e.g. salad)

Homogenous Mixtures or Solutions occur when one substance
dissolves into another and appears as one. (e.g. sugar water)
Elements and Compounds

Elements are pure substances that are not easily broken down (e.g.
hydrogen)

All Elements are made of tiny units called atoms. Atoms have smaller
charged particles called Protons (+), Electrons (-) and Neutrons (+/-)

Protons and Neutrons are found in the Nucleus of the item and the
Electrons move around the nucleus in specific orbits. The first ring
around the nucleus is limited to 2 electrons, followed by 8 in the
second, third, and so forth. Elements are most stable with 8 electrons
in their outer valence (e.g. Noble gases)

Bohr-Rutherford Diagrams are used to show the number and specific
arrangement of electrons in an element.

Compounds is a pure substance that is made of 2 or more elements
in a particular ratio (e.g. Sodium Chloride Na+ + Cl- → NaCl)
The Periodic Table
The Table Divided


The elements in the periodic table are arranged by atomic number.
Rows are called periods.

Columns are called groups or families.
electron valence.
They share a common

If expressed in standard notation as in the sodium atom below,
along with the symbol (Na) and common Ionic charge (+), it has the
atomic mass (23) (weight when compared to a carbon atom) and
the atomic number (11) which is also the number or protons in the
nucleus and electrons in its orbit.

To determine the amount of neutrons, subtract the atomic number
from the mass number (12) (what is left of the 23 particles in the
atom assumed to be neutral).
The Table Continued…
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The table is divided into several groups or families.

The most common groups are metals, non-metals, and metalloids.
Properties of Metals

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Metals are good
conductors of heat and
electricity.
Metals are shiny.
Metals are ductile (can be
stretched into thin wires).
Metals are malleable (can
be pounded into thin
sheets).
A chemical property of
metal is its reaction with
water which results in
corrosion.
Properties of Non-Metals

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Sulfur
Non-metals are poor
conductors of heat and
electricity.
Non-metals are not ductile or
malleable.
Solid non-metals are brittle
and break easily.
They are dull.
Many non-metals are gases.
Properties of Metalloids
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Silicon
Metalloids (metal-like)
have properties of both
metals and non-metals.
They are solids that can
be shiny or dull.
They conduct heat and
electricity better than
non-metals but not as
well as metals.
They are ductile and
malleable.
The Bohr-Rutherford Diagram

As mentioned before, these diagrams are used to show the number
and specific arrangement of electrons in an element.

In the nucleus, place the element symbol in standard notation. This
will easily allow you to determine how many valence electrons the
element has.

The amount of electrons in the outer valence determines how
reactive an element is (e.g. sodium is very reactive with water)
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http://www.youtube.com/watch?v=dmcfsEEogxs

These are some examples of B-R diagrams. Copy the correct format
from the blackboard.
Check Your Understanding

Complete the following questions from your textbook:

#1-4 on page 163.

#1-6 on page 167.

#1-4 on page170
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A, B D-F on page 166.