 Chemical Reaction-A change in which a substance (or substances) is changed into one or more new substances.  The electrons are atoms that are affected in a chemical reaction. 1K9HmKmUUC&pg=PA206&lpg=PA206&dq=what+part+of+the+atoms+are+affected%3F&source=web&ots=zUnCZPRTl0&sig=- ak0AkzhoeUDd8IbhmCYOri4s8M&hl=en&sa=X&oi=book_result&resnum=7&ct=result  During a chemical reaction one or more bonds between atoms or molecules are either broken down or new ones are formed. Bonds are broken and formed by the interaction of electrons.

 Reactants-A chemical reactant is any substance that is directly involved in a chemical reaction. Though catalysts are necessary for many chemical reactions to take place, they are not consumed in the reaction and therefore are not classified as reactants.  Products-substances newly formed are called products. Physical appearances of products are often different from reactants. Chemical reactions are often accompanied by the appearance of gas, fire, precipitate, color, light, sound, or odor.  The law of conservation of mass relates to a chemical reaction when we light a match, start a car, eat dinner, or walk the dog. mahathera.wordpress.com/fighting-fire /

* Energy Reaction- Energy released or absorbed during a chemical reaction. Release large amounts of heat energy. Example- when a mixture of hydrogen gas and oxygen gas in a glass jar is ignited by a spark, rapid and large amounts of heat energy are released shattering the glass jar in the process. * These chemical changes, are always accompanied by a change in energy. That means that either energy is given off during the reaction, or energy is taken in =

* The chemical potential energy is: The energy in chemical bonds holding the atoms of a compound together. Food, wood, batteries, and fossil fuels contain chemical potential energy. * Activation energy: The amount of energy required for a chemical reaction to take place. * Exothermic Reaction: Heat that is required for a chemical reaction to take place. Some examples of an exothermic reaction is fire. If you mix something with fire then an exothermic reaction might have taken place. * Endothermic Reaction; Cold air that is required for a chemical reaction to take place. An example of this is ice. When you mix something into ice then maybe an endothermic reaction took place.

* A combustion reaction occures when you mix water and carbon dioxide. * To tell the different types of reactions by looking at the chemical formula is to look at the energy level. This shows that when a reaction occurs the energy level increases.

* Synthesis: Was first developed in ancient greek. Now we use it in many fields,usually that combinds pre-existing elements resulting in the formula. * Decomposition: refers to process by which the tissue of a dead orgasm, breaks down into simpler forms of matter. Such a breakdown of dead organisms is essential for growth and development. Decomposition is the separation of a chemical compound into elements or smaller compounds.

 Combustion: An experiment that either explodes of has a chemical reaction. For Example: When wood burnes, It must do so in the presence of 02 and a lot of heat is produced. * Single Replacement: This occures when two cations are combined. If we mix zinc with silver nitrate a single replacement will occure. * For Example: Go to this Url and it shows an example of a single replacement. * Double Replacement: Both the cation and the anion of two different compounds switch places. *For example: When two ionic compounds are mixed together a double replacement occures

 Types of chemical reactions are: Chemical Decomposition Single Displacement Organic reactions Organic reactions are : Anything Compounds are decomposed that is living,and and anything into Different elements. That does not produce energy. Elements being displaced out of a compound by more elements. reactive compounds.

This picture shows how a chemical reaction occures, and what happens when the reaction takes place. URL: