1. Matter:
Chemical Properties

2. Becoming Something New
-chemical properties describe a substance based
on its ability to change into a new substance with
different properties
-Examples:
Wood burns (makes ash and smoke; 2 new
substances with different properties)
-ability to burn is called flammability and is a
chemical property

3. Something New Continued
-other examples:
reactivity with
-oxygen
-acid
-water
-reactivity: something happens
when one substance comes into
contact with another substance
-chemical properties can be
observed by the senses, but usually
only during or after a reaction

4. Steel rusts Paper burns An egg can be cooked -all examples of
chemical properties
-chemical properties and physical
properties are characteristic
properties
-always the same for a
particular substance
An egg can be
cooked

5. Physical and Chemical Changes
-a physical change affects one or more physical
properties of a substance
-Example: ripping a piece of paper
no matter how many times you
rip it, it's still paper
-more examples:
melting, freezing, dissolving,
bending, cutting, crushing
-a physical change can be undone because the
identity of the substance remains the same
-Example: a stick of butter will melt if left out, but
will return to its solid state if put in the
refrigerator

6. -a chemical change occurs when one or more
substances are changed into new substances with
different properties
-Example: baking a cake
-each ingredient has its own properties
-when mixed together and baked something new and
different forms
-heat interacts with ingredients to cause a chemical
change
-many chemical changes require heat

7. More Examples
-soured milk, hot gas from the combustion of fuel, oxidation of metals, fizzing of alka-seltzer
-most chemical changes cannot be undone because it is not possible to separate the ingredients using physical means (you can't un-bake a cake!)
-some chemical changes can be reversed under the proper conditions and using other chemical changes

8. Look for Clues Watch the BrainPop Try the quiz
-chemical changes can be
recognized by the clues they give
*color change
*fizzing (release of gas bubbles)
*produce heat, light, sound or odor
*a precipitate forms
Watch the BrainPop
Try the quiz