aim: how do physical and chemical changes differ? do now: writing activity hw: handout

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.