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| Chemical Reactions |
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Chemical reactions are a specific course of actions that lead to the changing of one of the sets of chemical substances. When two or more chemicals interact with each other their atoms become bonded together forming a chemical compound. Most noted, chemical reactions involve the changes in the motion of the atoms electrons, which form a bond, and change their physical make up. These reactions are studied in labs all over, and are vital to the ongoing research and development of hundreds of different products.
Chemical reactions are separated into two different types. A non-spontaneous chemical reaction requires for there to be some form of energy input, like heat, electricity or light. The process can only produce results when one of these forms of energy is added. A spontaneous chemical reaction does not require any input of energy to produce results. The chemical reaction happens right away, as soon as the two or more are mixed together. The differences in the energy released is compared to the energy they had as individual elements, so this is how they determine if the reaction was a spontaneous or non-spontaneous.
Chemical reactions are always followed by a change in energy. Some reactions have to absorb heat from their environment to proceed. These types are called endothermic. A cold pack is a very common example of this type of reaction. The pack contains two chemicals, urea and ammonium, when the bag is squished together, the reaction needs to draw in heat, therefore, causing the bag to become cold. The other type is called exothermic; 'Exo' meaning 'exit' or 'go out' and 'Thermic' meaning 'energy' or 'heat' These types need to release energy back into their environment. Chlorine and sodium elements are an example of this reaction process. When they are mixed together, the chemical reaction is so strong that you can see flames.
A breakthrough occurred in the late 1890's when Scottish chemist Sir William Ramsay discovered the chemical elements; neon, argon, helium, xenon and krypton. He discovered that these chemicals do not react with other chemicals, and therefore they were assigned the nickname 'inert/ or 'noble'. The reason that these chemicals have no reaction with others is because of their electron configurations. All the inert gases have what is called a full 'valence shell' meaning that they are stable with basically no room for any reactions to take place. On the flip side, the reason that other chemicals react with one another is because they are trying to get to that state of having a 'full valence'.
Chemical reactions that produce immediate results, such as the above mentioned chemicals, are spontaneous reactions. On the hand, not all reactions are spontaneous such as a match. You must first apply outside energy to strike the match along the rough line on the matchbook. After an input energy is applied, the match will produce the reaction in the form of a flame. The reaction is between the oxygen and the chemical makeup of the match head. This is a non-spontaneous reaction because the two elements had to have input energy in order for the reaction to take place.
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