Physical and Chemical Changes

Everything that has mass and volume is called matter. Everything is made of matter

Matter has properties  Two basic types of properties that we can associate with matter. Physical properties Chemical properties

What are properties? h  Characteristics used to identify, describe and classify matter  Two basic types of properties of matter are : Physical properties and Chemical properties :

Physical Properties  Characteristic of a substance that can be measured/observed (using your senses) without changing the substance into something else. HardnessTextureColor OdorTasteTemperature

More EXAMPLES - Physical  size, shape, freezing point, boiling point, melting point, density, mass, volume, Physical State (solid, liquid or gas) magnetism, viscosity, density, luster and many more. Viscosity - The resistance of a liquid to flowing. Examples: Low viscosity-water, rubbing alcohol High viscosity-honey

Chemical Properties  Chemical properties are characteristics involved when a substance interacts with another substance to change its chemical make-up. FlammabilityRustingCreating gas bubbles Creating a new chemical product Reactivity with water pH

Alike? Different?  Draw a double bubble map in your notes to compare and contrast physical and chemical properties.

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  Physical changes occur when matter changes its property but not its chemical nature.  Physical property changes could include a change in: texture, shape, size, color, volume, mass, weight, and density.

Examples of Physical Changes  Boiling  Freezing  Dissolving  Breaking  Making a mixture 2 or more types of matter (substances) mixed together Not in specific amounts Can be separated physically

Chemical Change  Chemical changes are changes matter undergoes when it becomes new or different matter.  To identify a chemical change look for signs such as, bubbling and fizzing, light production, color change with an odor, smoke, and presence of heat.

Evidence of a Chemical Change Formation of gas Formation of precipitate ( a solid that results from two liquids reacting ) Change in color Change in energy  Endothermic Absorbs heat energy (gets cold)  Exothermic Releases heat energy (gets hot)

The type of change that occurs in matter depends on the type of properties that are changed. Physical changes change physical properties only Chemical changes change chemical properties and physical properties

Chemical Changes  The composition of the substance changes. The substances present at the beginning of the change are not present at the end; new substances are formed. The change cannot be “undone.”

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 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?  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.