Chemical Reaction Notes PDF

Chemical Reaction Notes A chemical reaction is a process that changes one set of chemicals into another set of chemicals. Chemical reactions consist of reactants and products. Reactants enter the reaction whereas products are the result of the reaction. Ex.  CO2 + H2O...

Chemical Reaction Notes A chemical reaction is a process that changes one set of chemicals into another set of chemicals. Chemical reactions consist of reactants and products. Reactants enter the reaction whereas products are the result of the reaction. Ex.  CO2 + H2O H2CO3 reactants product Chemical reactions always involve the breaking of bonds in reactants and the forming of new bonds in the products. Chemical reactions are either exothermic or endothermic. Exothermic reactions release energy. Endothermic reactions absorb energy. Enzymes – These are proteins that act as biological catalysts. A catalyst speeds up the rate of a chemical reaction. They do this by lowering the activation energy of a reaction and thus increasing the likelihood that a reaction will occur. Enzymes are very specific generally working with only one chemical reaction. Because of this, the name of an enzyme is usually derived from the reaction that it catalyzes. Example: In the reaction CO2 + H2O H2CO3 , the enzyme in this reaction is called “Carbonic Anhydrase”. In the reaction, carbonic acid is formed as the product and water is removed. Enzymes also have a “-ase” ending to them. When a chemical reaction occurs, the reactants collide. An enzyme provides a “meeting site” for this collision to occur. When reactants are used in an enzyme-catalyzed reaction, the reactants are referred to as substrates. Where the meeting occurs is called the active site. enzyme substrates product active site After the reaction occurs, the substrates are released from the active site as a product. Notice how the substrates fit like puzzle pieces into the enzyme’s active site. This active site is specific to these two reactants. This is why the shape of a protein is so important. Enzymes can be affected by a variety of conditions. Some enzymes are affected by pH levels, whereas others may be affected by temperature. When an enzyme loses its shape, we say that it has become denatured. Other molecules called inhibitors can also affect the rate of a chemical reaction. They do so by competing for the enzyme’s active site and blocking it from the normal substrate.