chapter 11 - HEAT AND CHEMICAL CHANGE. ELEMENTS

In this chapter we will explain the heat and chemical change. The application of heat to certain substances causes only physical changes in which new substances or substances are not formed. When heat is applied to a specific substance, chemical reactions or chemical reactions may occur in which one or more new substances having different properties from the original substance are formed. The decomposition of water occurs during electrolysis, where the current passes through a solution containing a small amount of sulfuric acid. This element is a pure substance that has never been converted into a chemically simple substance. When two or more elements are combined in a chemical change, they form a compound. Pure substances are elements or compounds. Impurities consist of two or more elements or mixtures of compounds

Chemical changes produce one or more substances that are quite different from the original material. Elements and / or compounds at the start of the reaction are rearranged to new product compounds or elements. Chemical changes change the composition of the original material. At the end of the chemical change there are various elements and compounds. The atoms in the compound are repositioned to create new and different compounds.

Chemical reactions, also called chemical reactions, are the process of transforming one or more substances into one or more new, different substances. In other words, chemical changes are chemical reactions including rearrangement of atoms. Normally, physical changes can be reversed, but chemical changes do not occur unless more chemical reactions pass. As chemical changes occur, the energy of the system also changes. The chemical change of heat is called an exothermic reaction. Endothermic reaction

If heat is released during a chemical change or reaction, it is called an exothermic reaction. When heat is absorbed by chemical changes and reactions, it is called endothermic reaction. The rate at which the chemical reaction takes place depends on the temperature and pressure and the concentration of the substance involved in the chemical reaction. Substances, sometimes called catalysts, are used to promote or encourage chemical reactions. Light useful for film processing

According to the law of thermodynamics, all chemical reactions change the energy state of reactants. As the reaction progresses, energy changes are caused by changes in the number and strength of chemical bonds. Reaction heat is defined as the amount of heat released or absorbed during a chemical reaction. If heat is released or released during chemical conversion, the reaction is called exotherm. Alternatively, in an endothermic reaction, heat is absorbed as the reactants are converted to products. In an endothermic reaction, thermal energy must be supplied to the system to react, and the heat content of the product is greater than the heat content of the reactant. For example, when a mixture of hydrogen gas and oxygen gas is spotted, water is formed and thermal energy is released. The chemical reaction is an exothermic reaction, and the heat content of the product is lower than the heat content of the reactant.