Topic: Chemistry
Aim: Describe the properties and
different types of mixtures.
Do Now: 1. Take out Density ISA
2. CONTRAST elements and
compounds.
HW: Mass, Temperature and Density
Exam Review Sheet
1. Identify the structure with the
greatest density. Support your
answer.
Bolt because it sank all the
way to the bottom.
2. Identify the structure with the
smallest density. Support your
answer.
Ping pong ball because it is
floating at the top.
3. Identify the liquid that is the
least dense. Support your
answer.
Lamp oil because it is at the
top.
4. Identify the liquid that has
the greatest density.
Support your answer.
Honey because it is at the
bottom.
5. Which is least dense: the
milk or the rubbing alcohol?
Support your answer.
Rubbing alcohol because
it is above milk.
Which scenario represents a chemical
change? Support your answer.
Mixtures
Mix of dissolved
substances such as salt,
fluoride, calcium
carbonate, magnesium,
iron, etc…
Pure substance –
made up of just
water molecules
• 2 or more substances PHYSICALLY
MIXED together but NOT
CHEMICALLY COMBINED
• Ex:
– Soil
– cake batter
– cereal with milk
– Vinegar
– Concrete
For example powdered iron and powdered sulfur
mixed together makes a mixture of iron and sulfur.
They can be separated from each other without a
chemical reaction, in the way that different colored
sweets can be picked out from a mixed packet and
put into separate piles.
So… what is the main difference between a
compound and a mixture?
In a compound, substances are CHEMICALLY
COMBINE.
In a mixture, substances are NOT CHEMICALLY
COMBINED. They are PHYSICALLY
COMBINED!
A
B
C
Distinguish the element, mixture and compound.
Support your answer.
Milk is a
combination of
water, sugars,
proteins, and fats
making it a mixture.
Sugar solution
A sugar solution is
a combination of
sugar and water.
Jello consists of
gelatin and water.
Vinegar is a
combination of acetic
acid and water.
Solutions
• Mixture that contains small and
dissolved particles
Parts of a solution
• Solute:
substance
dissolved
• Solvent:
substance
that
does the
dissolving
Identify substances A
and B.
A
B
A soft drink is a solution that contains
several dissolved substances in water.
Solubility
• How well a solute dissolves
Soluble substance
• Dissolves in another substance
– Ex: Salt and sugar dissolve in water
Sugar
water
solution
Salt water
solution
Insoluble substance
Sugarsubstance
• CANNOT dissolve in another
water
solution
Ex: oil
Obviously NOT soluble in water!!!!
A lava lamp depends on
the globs not being
soluble. It also
depends on the globs
being about the same
density as water. It
took years to develop
the right ingredients
to make a lava lamp
work.
Factors that affect solubility
1. Temperature: As temp of solvent
increases, solubility of the solute
increases
2. Particle size: the smaller the
size, the greater the solubility
powdered sugar
sugar granules
3. Stirring: increases solubility
Let’s summarize…
1. Explain what makes up a mixture.
2. Describe the difference between a
compound and a mixture.
3. Explain what a solution consists of.
4. Identify the factors that affect solubility.
Review:
Which of the following is an example
of a mixture of gases?
1. soft drink
2. air
3. oxygen
4. water
In sweetened tea, the sugar is
called the
1. solute.
2. solvent.
3. colloid.
4. solution.
Which of the following would help
sugar dissolve faster in water?
1. stirring the water
2. decreasing the solubility of sugar
3. using larger particles of sugar
4. decreasing the water temperature
Which statement is true regarding
insoluble substances?
1. They can be easily dissolved in a
solvent.
2. An example of an insoluble substance
is ice tea dissolving in water.
3. Insoluble substances cannot dissolve
in a solvent.
4. They can easily dissolve in a solute.
Chemical change
Physical change
Chemical change
Chemical change
Tarnishing of
silver
Chemical
change
Tarnish is silver
sulfides that
form from sulfur
compounds in
the air.
Element or compound?
1. NaCl Compound
2. O Element
3. C6H12O6 Compound
4. CO2 Compound
5. O2 Molecule