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Properties of Matter
Section 4.2 of the textbook
pp. 149 -155
Physical Properties
• Physical properties are characteristics
or descriptions of a substance that may
be observed or measured.
• The substance remains the same, it is
not made into a new substance, when
you observe physical properties.
Physical Properties
• In determining the properties of a
substance, you make qualitative or
quantitative observations.
Quantitative Observations
Quantitative observations – observations
made using tools to measure various
properties of a substance numerically.
e.g. temperature, volume, mass, length,
density
Qualitative Observations
Qualitative observations – observations
that are descriptive and require no
measurement. They are usually
determined through the use of your
senses (sight, smell, taste, touch or
hearing).
**Using the senses of taste, touch and
smell may be hazardous!! WHY?
Physical Properties of Matter
Colour – is observed with your sense of sight,
and is related to the reflection of different
wavelengths of light off of the surface of an
object.
E.g. a green object is reflecting green light
which reaches your eye. For more info, go to this website:
http://www.artsparx.com/seeingcolor.html
Colour vision
When you see colour,
you are seeing the
light that reflects from
an object.
The lemon reflects
yellow light and
absorbs the other
colours of light.
Physical Properties of Matter
Texture – observed using your sense of
touch. It is how a substance feels.
Examples of textures are scratchy,
rough, bumpy, smooth.
If the substance being observed is sharp,
poisonous or corrosive, it will be dangerous to
observe this property.
Check with your teacher first
Physical Properties of Matter
Lustre – the visual property of how well a
substance shines with reflected light.
There are 2 descriptors for this property:
Shiny – the substance reflects light well
Dull – the substance does not shine with
reflected light.
Physical Properties of Matter
Clarity – the ability to see an object or light through another object.
There are three degrees of clarity:
Clarity
1. Transparent – able to see an object
and light through the object without
obstruction.
May be described as
clear.
Clarity
2. Translucent - allowing light to pass
through but diffusing it so that objects
on the opposite side are not clearly
visible, but are still
slightly visible. The
circle shown here
is translucent.
Clarity
3. Opaque – not allowing light or an
image to be seen though.
The grey side
of this oval is
opaque.
Physical Properties of Matter
State of Matter – this property
relates to the shape and volume
occupied by substances. The state
is related to how the particles in an
object are connected together.
State of Matter
Solids – maintains its shape and volume, no
matter what type of container they are placed
in. The particles pack together tightly.
State of Matter
Liquids – maintain their volume but will change
to take the shape of their container
State of Matter
Gases – take on the shape and volume of (will
fill up) their container. The particles move
quickly and randomly.
State of Matter
Physical Properties of Matter
Hardness – the ability of an
object to resist being scratched.
This property is observed by
comparing two substances.
Hardness
Objects may be hard (can scratch another substance) or soft (able to be scratched).
E.g. If a diamond is rubbed on a mirror with enough force it may scratch the mirror. The diamond is hard, and the mirror is soft.
Physical Properties of Matter
Malleability – the ability of metals to be
hammered into thin sheets, or to be
shaped (bent) without breaking.
Objects may be malleable (bendable,
e.g. aluminum) or brittle (will break on
bending, e.g. chalk)
Physical Properties of Matter
Ductility – the ability of a metal to be
stretched into a long wire.
The most ductile metals are gold, silver,
aluminum and copper.
Physical Properties of Matter
Melting Point – the temperature at which
a solid will become a liquid.
E.g. The melting point of gold is 1064 degrees Celcius
Physical Properties of Matter
Boiling Point – the temperature at which
a liquid becomes a gas.
E.g. the boiling point of gold is 2856 degrees Celcius
Physical Properties of Matter
Crystal Form – a description of the
shape of solid crystal substances.
There are a number of different shapes,
but in this course we are concerned with
only 4 crystal forms:
Crystal Form
Cubic
Crystal Form
Granular (irregular)
Crystal Form
Powder
Crystal Form
Hexagonal
Physical Properties of Matter
Solubility – the ability of a substance
(called a solute) to dissolve in another
substance (called a solvent).
Substances that dissolve are soluble.
Substances that do not dissolve are
insoluble.
Physical Properties of Matter
Viscosity – the resistance of a liquid to
flow or pour.
High viscosity liquids pour very slowly
(with high resistance to flow).
Low viscosity liquids pour very easily (with
low resistance to flow).
Viscosity
Low High
Physical Properties of Matter
Density –compares the mass to the volume of a substance (mass by comparison to size).
Density is important in determining buoyancy of one substance in another. An object must be less dense than other to float.
Density
The green liquid
is less dense
than the blue
liquid. Which
liquid is the
most dense?
Physical Properties of Matter
Conductivity – the ability of an object to carry electricity or heat. Most metals are good conductors.
A conductor carries heat or electricity well.
An insulator does not carry heat or electricity well.
Chemical Properties of Matter
Chemical properties are characteristics or
descriptions of an object determined by
reacting the substance with another
substance.
To determine chemical properties, the original
substance may be changed into a new
substance with different properties.
Chemical Properties of Matter
Combustion – the ability of an object to
burn.
In combustion reactions, a substance
burns in the presence of oxygen (the
substance reacts with oxygen in the air).
Combustion
Chemical Properties of Matter
Reaction with Acid – an object may
change its form or react (e.g. dissolve,
bubble, explode, release heat) in the
presence of acid.
Not all substances react with acid.
Light Sensitivity
Some chemicals are so unstable, that they will get enough energy from light to make them break down into other substances. Hydrogen peroxide and some prescription drugs will do this.
If the label says keep in a dark place, it is for this reason.
Light Sensitivity
Reaction with Other Chemicals
When different chemicals react, they will
produce new substances with obviously
different properties
• e.g. new gas
new colour
energy is released (heat, sound, light)
energy is absorbed (feels cold)
new solid produced (precipitate)