Chemical Property A chemical property is a property of matter that describes a substances ability to participate in a chemical reaction. A chemical change occurs when the substance changes into something new with new properties.

Chemical Property Flammability Is the ability to burn Examples: wood, paper, alcohol Chemical properties are not always easy to detect.

Chemical Properties The way a substance may change or react to form other substances: some examples are Reactivity with water Reactivity with oxygen (oxidation) Reactivity with acid Chemical properties of matter describes its "potential" to undergo some chemical change or reaction by virtue of its composition. What elements, electrons, and bonding are present to give the potential for chemical change. It is quite difficult to define a chemical property without using the word "change". Eventually you should be able to look at the formula of a compound and state some chemical property. At this time this is very difficult to do and you are not expected to be able to do it. For example hydrogen has the potential to ignite and explode given the right conditions. This is a chemical property. Metals in general have they chemical property of reacting with an acid. Zinc reacts with hydrochloric acid to produce hydrogen gas. This is a chemical property.

Characteristic Properties Scientists use these properties to identify and classify substances. They are always the same no matter what size the sample is. They can be physical properties like density and solubility or chemical properties like flammability and reactivity.

What is a Chemical Change? When a substance undergoes a chemical change, it is changed into a different substance with different properties. Example: Baking a Cake

Examples of Chemical Changes Every time you use a battery a chemical change takes place. Every time you eat—food is digested a chemical change takes place. Electrolysis- is a process by which water is broken down into hydrogen and oxygen gas.

Clues to Chemical Changes Could make a sound Could give off light Change in odor Change in color Could Fizz or foam the object or liquid could give off heat

Signs of a Chemical Change Color Change Changes in Characteristic Properties (odor, light given off)

Signs of a Chemical Change Gas Production Temperature Change

How do I know if a Physical Change occurred or a Chemical Change occurred? The most important questions to ask is did the composition/identity of the substance change?

Can Changes Be Reversed Some physical changes are easily reversed but not all. Chemical changes cannot always be reversed-sometimes with a chemical reaction we can get the original substance back