Transcript chemistry review - sowerbyscienceswc

CHEMISTRY REVIEW
MATTER
What is Chemistry
• Chemistry - the study of the structure,
composition and properties of matter &
how matter interacts with other matter
• Matter – anything that has mass and
occupies space (has volume)
PROPERTIES OF MATTER:
Physical Properties
 Can be determined without altering chemical composition of the
substance.
• Qualitative properties are observed with the senses (not measured).
• Ex. colour, odour, taste, lustre, malleability, ductility, viscosity, form, texture.
• Quantitative properties are numerical measurements.
• Ex. density, boiling/melting point, solubility, volume, weight.
Chemical Properties
 Describe how matter behaves in the presence of other substances,
or when subjected to fire, heat, light, pressure or electricity.
Ex. - magnesium reacts with hydrochloric acid to produce hydrogen gas
- glass does NOT react to this acid
Classifying Matter
MATTER
Made of more than
1 component…
Made of 1
component…
Pure
Substances
Elements
Has one kind
of atom.
Eg. Copper,
gold, oxygen
Compound
Has more than
one kind of atom
bonded in a fixed
ratio called a
molecule
Eg. Water, CO2
Mixtures
Homogeneous
Contains one
evenly mixed
‘phase’ – looks
like 1 thing.
Eg. Solution
Heterogeneous
Contains more
than one unevenly
mixed ‘phase’ –
you can see the
individual parts.
The Periodic Table
The Periodic Table
• There are 118 elements on the Periodic
Table. 92 of them are naturally occurring.
• All matter in the universe is made up of at
least 1 element.
How is it Organized?
Periods: (horizontal rows)
• Numbered 1-7
• Each period represents an energy level where
electrons can be found
• Counting across a row to an element’s location
tells how many electrons are in its outer shell
Groups or families: (vertical columns)
• Groups are numbered from 1-18
• Group members have similar chemical
properties which get stronger as you go down a
column. Eg. Alkali Metals
How is it Organized?
Metals & Non-metals
• Metals are on the left side
• Non-metals are on the right side
• Exception: Hydrogen (H) is a non-metal
• Metalloids are the elements that are
between the metals and non-metals – they
have some properties of both.
Properties of Metals & Non-metals
Properties of metals
Properties of non-metals
• High lustre (shiny)
• Most are grey or silver in
colour
• Malleable (hammer into
sheets)
• Ductile (stretch into wire)
• Good conductors of
heat and electricity
• Most are solids at room
temp…except Hg…it’s a
liquid!
• Low lustre (dull)
• Various colours (including
colourless)
• Brittle (shatter when
hammered)
• Not ductile (shatter when
stretched)
• Poor conductors (are
insulators)
• Mostly solids and
gasses at room temp.
METALS
NON-METALS
Main group elements:
Groups 1,2,17 and 18
Alkali metals: Group 1
– very soft, very reactive, one valence electron
Alkaline earth metals: Group 2
– somewhat soft, somewhat reactive, two valence
electrons
Halogens: Group 17
– very reactive non-metals, one short of a full set
of valence electrons, diatomic molecules
Noble gases: Group 18
– almost completely un-reactive or inert, full
valence shell. Exist as monatomic gases
ATOMIC STRUCTURE REVIEW
• A chemical Symbol represents 1 atom of
an element. eg: Al
• Atoms are not solid spheres as first
thought, the majority of an atom is empty
space! What gives matter “solidness” is
the tiny subatomic particles that make up
atoms.
• There are three types of subatomic
particles:
Sub-atomic Particles
Particle Symbol
Location
Charge
Size
Proton
P
In the
nucleus
Positive
1
Electron
E
In the orbitals
(shells) around
nucleus
Negative
0
Neutron
N
In the
nucleus
Neutral
1
Back to the Periodic Table
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C
CARBON
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This is the Atomic
Number or A
This is the Symbol
This is the Element’s
Name
This is the Atomic
Mass or Z
And now the short form…
A
(Atomic Number)
Z
(Atomic Mass)
OR…
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CARBON (C)
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Bohr-Rutherford Diagrams
Outer shell (orbital / energy level)
called the Valence shell
Maximum # of electrons at
each energy level
(inner to outer) 2, 8, 8…
The Nucleus contains
protons & neutrons
How to Draw a Bohr-Rutherford
Diagram
• First you need to determine how many
protons, electrons and neutrons you
have: (PEN)
• Look at the Periodic Table:
• The atomic number = the number of protons (+) &
the number of electrons(-) (# of + = # of -)
• The atomic mass can help you determine the
number of neutrons:
(Neutrons = atomic mass – atomic #)
• All that’s left is to draw the diagram!
How to Draw a Bohr-Rutherford
Diagram for ANY Element.
1. Figure out how many protons, electrons and
neutrons there are in one atom of the element.
2. Draw the nucleus (a small circle).
• Inside the nucleus write the number of protons
and neutrons.
3. Calculate the number of orbitals you will need
by following the limits on the number of electrons
each orbital can have.
4. Draw the orbitals as rings around the nucleus.
5. Draw the electrons (as coloured-in circles) on
the orbitals.