Uploaded by Oluwadare Olalekan

elements compounds mixtures

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How can you determine whether
something is an element or not?
They are all listed on the periodic table.
ELEMENT
SONG
1. Pure substance
– Made of only 1 type
of particle
– Ex: copper wire only
has copper atoms
2. Can’t be separated
into simpler
substances by
chemical or physical
means
3. Each has a unique
set of properties
– Called characteristic
properties
– Can be physical or
chemical
4. Classified by their
properties
1. Metals
2. Nonmetals
3. Metalloids
Elements
Metalloids
Metals
Nonmetals
Develop the concept map by adding
info. about metals, nonmetals, &
metalloids
METALLOIDS
METALS
•Shiny
NONMETALS
•Characteristics of
metals and nonmetals
•Good conductors
•Dull (no shine)
•Malleable
•Poor conductors
•Semiconductors
•Ductile
•At room temp, only a
few are solids that are
brittle
•Ex: silicon, germanium
•Ex: gold, silver,
copper
•Most are gases
•Ex: hydrogen,
oxygen, helium
Use placement on the Periodic
Table to classify elements
•
•
•
Do you know any compounds?
How are they different from elements?
Characteristics
1. Found in nature more often than pure elements
2. Have more than one element
3. Elements are chemically bonded to each other
–
Mg + O2 makes MgO
4. Pure substances that occur in fixed ratios by mass
–
1g H to 8g of O in every water molecule
5. Can’t be separated by physical means
6. Have their own unique set of properties
CLASSIFICATION OF MATTER
Mixtures
•
•
2 or more substances that are not chemically
bonded
– So diff parts keep their own properties
Ex:
–
–
–
–
–
•
pizza
granite
Kool-aid
Brass
Jello
Parts do not occur in a definite ratio
– Compare the 2 pepperoni pizzas
Mixtures
•
Can be physically separated by
1.
2.
3.
4.
5.
Distillation
Magnet
Centrifuge
Filtration
Evaporation
ELEMENTS
COMPOUNDS
MIXTURES
Mixtures
•Can be heterogeneous (see diff pieces) or
homogeneous (uniform appearance)
•Homogeneous mixtures are called solutions
•Heterogeneous mixtures include suspensions
•Colloids are classified as heterogeneous in some
books and homogeneous in others
•
•
•
Solutions – look the same throughout
From Chem4kids
How much solute can
dissolve in water?
Solubility graph can tell you
1. Most compounds show
a(n) ________ in
solubility as temp. inc.
2. Which compound shows
the greatest increase in
solubility as temp inc?
3. Which compound(s)
actually dec in solubility
as temp inc.?
4. How much potassium
nitrate will dissolve in
100 ml of water at 40oC?
5. How much sodium
nitrate will dissolve in
100 ml of water at 90oC?
Solubility Graph
1. Which compound
shows the greatest
increase in solubility as
temp inc?
2. Which compound(s)
actually decrease in
solubility as temp inc.?
3. Which compound has
the highest solubility at
58oC?
Fill-in the Venn
diagram with
characteristics.
•Ex:
Koolaid, salt
water,
brass
•Don’t scatter light/
light passes right thru
•Smallest solute
particles
•Do not settle out
Can pour
some
•Settle out on standing
•Pass thru filter
paper
•mixtures
•Separate w/filter paper
•Largest particle size (seen)
•Ex: blood, muddy water,
Italian salad dressing
•Scatter
light
•Medium particle
size
•Don’t easily pour
•Ex: Jell-o, fog,
milk, mayo,
whipped cream
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