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Aim: How do Physical and
Chemical Changes differ?
Do Now: writing activity
HW: handout
DO NOW: Writing Activity
• The students will describe the three states of matter and include the following :
• At least one example of each state
• A description of each state
MATTER• Matter is everywhere.
• Matter is anything that takes up space and has mass.
• Matter is constantly experiencing both chemical and physical changes.
Physical Change
• occur when matter changes its property but NOT its chemical nature.
• changes could include a change in:
texture, shape, size, color, odor, volume, mass, weight, and density.
Physical Change
Chemical Change
• are changes matter undergoes when it becomes new or different matter.
• To identify a chemical change look for signs such as color change, bubbling and fizzing, light production, smoke, and presence of heat.
Chemical Change• A chemical change
occurs when fireworks are used. Fireworks are made of metals such as magnesium and copper. These change chemically as they light up the sky.
Is it a chemical or physical
change?•Sugar dissolving
in tea
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•Logs burning
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•Breaking water up by
separating it into hydrogen and oxygen
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•Cutting paper
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•Crushing an
aspirin
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•Metal rusting
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•Lighter fluid
burining
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•An egg rotting
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Is it a chemical or physical
change?•An egg breaking
•Chemical Change
•Physical Change
OOPS!Did it change size, color, shape
(Physical Change)?or
Did it become different matter (Chemical Change)?
Correct!
Writing Activity• Write a paragraph about the difference
between a chemical and physical change. Give examples of each.
Aim: How do we read a solubility curve?
HW: HANDOUT
A solution is actually a type of mixture.
Think of the example of sand in water.
This is also called a "heterogeneous mixture."
Think of the exampleof salt water.
This is also called a "homogenous mixture."
DefinitionsDefinitions
A solution is a A solution is a homogeneous homogeneous mixture of 2 or more mixture of 2 or more substances that are substances that are uniform throughout.uniform throughout.
One constituent is One constituent is usually regarded as usually regarded as the the SOLVENTSOLVENT and and the others as the others as SOLUTESSOLUTES..
Parts of a Solution
• SOLUTE – the part of a solution that is being dissolved (usually the lesser amount)
• SOLVENT – the part of a solution that dissolves the solute (usually the greater amount)
Solute Solvent Example
solid solid Metal alloys
solid liquid Salt water
gas solid Moth balls
liquid liquid Alcohol in water
gas liquid soda
gas gas air
Solute + Solvent = Solution
DefinitionsDefinitionsSolutions can be classified as Solutions can be classified as
saturatedsaturated or or ununsaturatedsaturated and and super super saturatedsaturated
A A saturatedsaturated solution contains solution contains the maximum quantity of the maximum quantity of solute that dissolves at solute that dissolves at that temperature.that temperature.
An An unsaturatedunsaturated solution solution contains less than the contains less than the maximum amount of maximum amount of solute that can dissolve at solute that can dissolve at a particular temperaturea particular temperature
Solubility curve
Saturated
Unsaturated
Supersaturated
Solubility curve• Any point on a line
represents a saturated solution.
• In a saturated solution, the solvent contains the maximum amount of solute.
• Example
• At 90oC, 40 g of NaCl(s) in 100g H2O(l) represent a saturated solution.
Solubility curve• Any point below a line
represents an unsaturated solution.
• In an unsaturated solution, the solvent contains less than the maximum amount of solute.
• Example
• At 90oC, 30 g of NaCl(s) in 100g H2O(l) represent an unsaturated solution. 10 g of NaCl(s) have to be added to make the solution saturated.
Solubility curve• Any point above a line
represents a supersaturated solution.
• In a supersaturated solution, the solvent contains more than the maximum amount of solute. A supersaturated solution is very unstable and the amount in excess can precipitate or crystallize.
• Example
• At 90oC, 50 g of NaCl(s) in 100g H2O(l) represent a supersaturated solution. Eventually, 10 g of NaCl(s) will precipitate.
Solubility curve
Any solution can be made saturated, unsaturated, or
supersaturated by changing the temperature.