Observing+Chemical+Change

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media type="custom" key="6175171" TABLE OF CONTENTS! 1. Observing Chemical Change 2. Properties And Changes of Matter 3. Evidence For Chemical Change 4. Types of Chemical Reaction 5. Reversing Chemical Change 6. Resources

A chemical change is the same thing as a chemical reaction. They are both defined as a change in matter that produces one or more new substances. The burning of gasoline in a car's engine is a chemical change. The new substance that is formed comes out of the car's exhaust. Chemical changes happen everywhere. They happen all the time too. Another way to show chemical change is when you toast a marshmallow. The sugars and other substances will burn. They will produce a crust made of the new substances. Chemical change happens when you don't even know it (Frank, Little, Miller).

media type="custom" key="6197265" Properties And Changes of Matter Matter can be described in two terms of properties, physical and chemical properties. Changes of matter can be described in terms of physical changes and chemical changes (Frank, Little, Miller).​​

Matter has two different types’ properties. It has a chemical property, and also a physical property. A chemical property is a characteristic of a substance that describes it ability to change into other substances. An example of a chemical property is tarnishing the substance, and rusting. The other type property is a physical. A physical property is a characteristic of a substance that can be observed without changing the substance into a different substance. An example of a physical property is the color of the substance, Also the hardness, texture, shine, and flexibility of the substance (Frank, Little, Miller).​​

There are two different changes that matter can make. It can make a physical change, or a chemical change. A physical change is usually more visible, but they both happen weather you know it or not. A physical change is anything that alters the appearance. An example of a physical change is when you put an ice cube out of the counter for a long time and then you go back to check on it later, and it is water. The heat turned to solid ice into a liquid. The same goes for when you put a liquid into the freezer and it becomes a solid. The other type of change is a chemical change. A chemical change is a change in matter that produces one or more new substances (Frank, Little, Miller).​​

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Chemical change occurs when bonds break and new bonds form. Once the new bonds form a new substances are produced. Atoms form bonds when share or transfer electrons. An example of bonding can be when magnesium and oxygen react. An oxygen molecule has a double bond, and then the bond breaks. Each oxygen atom can accept two electrons after that magnesium and oxygen combine. A magnesium atom loses two electrons to an oxygen atom. Oppositely charged ions form. An ionic bond forms between the oppositely charged ions (Frank, Little, Miller).​​

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Evidence for Chemical Change One way to direct chemical reactions is to observe changes in the properties in the materials involved. When the properties go through a change, new substances are formed. Chemical reactions involve two main types of changes that you can observe. The changes are that a new substance is formed, and changes in energy (Frank, Little, Miller)​.​



There are a few types of changes to the properties of matter. One change is when a solid that’s forms from a solution during a chemical reaction. This change is called a precipitate. An example of this change is when you mix a liquid together with another substance and they react to form a solid. Another change that can happen to a solution during a chemical reaction is that the color can change. This is one of the more obvious changes in a reaction. AN example of this is like when you toast bread, or bake bread. You put the dough into the oven, and it is a white-ish color. You wait for a little bit of time, and the heat from the oven turns the bread brown. The heat changes the color in the bread while it bakes. The last change in property to something is the production of gas. If the reaction occurs in a liquid you might see it bubble. When is occurs in a solid there may be smoke. If you contain it in a bag, the bad may expand, or pop. All of these are changes in properties to a type of matter (Frank, Little, Miller).​​

There are many types of energies in everyday life, such as heat, light, and electricity. As the matter changes it can either be absorbed or released. When energy is absorbed it is called an endothermic reaction. The opposite of and endothermic reaction is an exothermic reaction. In and exothermic reaction energy is released in the form of heat. An example of an exothermic reaction is when an airplane flies in the air. Enough energy is released by the burning of the fuel to keep the plane moving fast enough to fly. There is either and exothermic or an endothermic reaction in a chemical reaction (Frank, Little, Miller)​.​

** Types of Chemical Reactions ** There are 3 different types of chemical reaction.

When you observe the chemical change you can write in an equation form. Reversing Chemical Change Some chemical changes can be reversed, some are really hard to and other don't even think about it, because its completely impossible (Newmark 13).
 * Synthesis- First it starts out single then turns into a more complex reaction.
 * __Decomposition__ - It starts out complex then becomes single, the opposite of Synthesis.
 * Spontaneous- This occurs naturally, it doesn't matter how long it takes, it will happen on its own time.

​ Resources

"FG08_04-04UN." //Chemical Reaction//. Web. 14 May 2010. .

Frank, Davud, John Little, and Steve Miller. //Prentice Hall Science Explorer//. Chemical Reactions. L. Upper Saddle: Pearson Education, 2009. 46-53. Print

"H2_O2." //BioJobBlog//. Web. 14 May 2010. .

"Myspace Comments." //Comment Haven//. Web. 14 May 2010. .

Newmark, Ann. //EyeWittness Science//. Chemistry. New York: Dorlins/Kindersly Inc, 1993. 13. Print.

Trefil, James. //Science and Technology//. New York: Routledge, 2001. 102. Print.

CORP, ZOHO, ed. "Marshmellows." Comic strip. Web.