Transcript Introduction to Chemistry

SNC1DE
Chemistry is the study
of matter and its
composition
 Discovery of
interactions between
different types of
matter (reactions)
 Properties of matter
can be manipulated for
use by man

Properties of matter
are characteristics that
help you describe and
identify matter
 Properties can be
described or measured
 Subcategorized into
physical and chemical
properties




Physical property is a
property that you can
observe without
changing one kind of
matter into something
new
Qualitative observations
are based on qualities of
the matter
Quantitative
observations can be
measured with a number
and unit
Qualitative includes:
1) Physical state
2) Colour
3) Odour
4) Crystal shape
5) Malleability
6) Ductility
7) Hardness
8) Brittleness
Quantitative includes:
1) Melting point
2) Boiling point
3) Density
4) Solubility
5) Electrical conductivity
6) Thermal conductivity
A chemical property is
a property that you can
observe when one kind
of matter is converted
into a different kind of
matter
 Example: A chemical
property of iron is that
is reacts with oxygen to
form rust

Qualitative includes:
1) Reactivity with water
2) Reactivity with air
3) Reactivity with pure
oxygen
4) Reactivity with acids
5) Reactivity with pure
substances
6) Combustibility
Quantitative includes:
1) Toxicity
2) Decomposition
QuantitySI
Definition
SI Units
Equipment used
Mass
The amount of
matter in an object
Grams
kg, g, mg, ug
Balance
Length
The distance
Metres
between two points m, cm, mm
Temperature
The hotness or
coldness of a
substance
Kelvin (K)
Thermometer
Degrees Celsius (oC)
Volume
The amount of
space an object
occupies
Cubic metre (m3)
Litre (L)
Millilitre (ml)
Beaker, graduated
cylinder, pipette,
calculated
Mole
The amount of a
substance
Mole (mol)
Calculated
Density
Mass per unit of
volume
Kg/m3
Calculated or
measured
Energy
The capacity to do
work (to move
matter)
Joule (J)
Calculated
Ruler
Significant digits are
used for accuracy and
precision
 Accuracy refers to how
close a given quantity
is to an accepted or
expected value
 Precision refers to the
exactness of a
measurement

Matter can be
classified as either a
gas, liquid, or solid
 Generally, as you add
energy, particles move
faster and farther apart
 As you remove energy,
particles move closer
and become attracted
to each other



1)
2)
3)
4)
5)
Chemical changes are
changes that alter the
composition of matter
Clues include:
Change in colour
Temperature change
Gas forms
Precipitate forms
Irreversible



Matter is either a pure substance or mixture
Pure substances have a definite composition,
has the same response to physical changes
Mixtures are a physical combination of two or
more kinds of matter


Elements are pure substances that cannot be
separated chemically into any simpler
substances
Compounds are pure substances that result
when two or more elements combine
chemically into a new substance


Heterogeneous mixtures are mixtures that
are visibly separate
Homogenous mixtures are mixtures that are
cannot be separated by eye