{"id":8074,"date":"2018-06-12T09:22:31","date_gmt":"2018-06-12T09:22:31","guid":{"rendered":"https:\/\/www.experimentoscientificos.es\/?page_id=8074"},"modified":"2024-11-20T13:06:10","modified_gmt":"2024-11-20T13:06:10","slug":"reacciones-quimicas","status":"publish","type":"page","link":"https:\/\/www.experimentoscientificos.es\/en\/reacciones-quimicas\/","title":{"rendered":"Chemical Reactions: Types and Examples"},"content":{"rendered":"
The chemical reaction<\/strong> is a process in which 2 or more substances are transformed to create new elements. To do this, they change their chemical bonds<\/a>its molecular structure, and sometimes the oxidation state<\/a>\u00a0of atoms.<\/p>\n The chemical reactions<\/strong> are a continuous part of our lives, and without them the Universe and the Earth as we know it would not be possible. From the reactions produced in the sun for the emission of light and heat, photosynthesis, reactions in the ocean, digestion of food, cleaning,..., everything corresponds to chemical reactions. That is why they are so important and why studying them on a small or medium scale helps us to understand life.<\/p>\n Depending on the modification that the reactants undergo, we can classify chemical reactions into different types of reactions. Each type of reaction has common elements, which we are going to see.<\/p>\n In addition reactions or so-called synthesis reactions, 2 or more elements are joined together to form 1 element. These reactions occur mainly in organic chemistry. The main feature of these reactions is that during the process, the double or triple bond is broken to form new bonds:<\/p>\n Example: C2<\/sub>H4<\/sub>\u00a0+ Br2<\/sub>\u00a0\u2192 C2<\/sub>H4<\/sub>Br2<\/sub><\/strong><\/p>\n A combustion reaction<\/a> consists of a substance reacting with oxygen to produce energy in the form of light and heat. They are always exothermic. A complete combustion requires a large amount of oxygen. Normally in combustion reactions the amount of oxygen is limited, the combustion is therefore incomplete and different resulting components (ashes and salts) are given. When an organic compound combusts completely, the result is always water and carbon dioxide:<\/p>\n Example. Methane gas combustion: CH4<\/sub>\u00a0+ 2O2<\/sub>\u00a0\u2192 2H2<\/sub>O + CO2<\/sub><\/strong><\/p>\n A decomposition reaction is a reaction that involves breaking a substance into simpler compounds. It is the opposite of an addition reaction. It can occur spontaneously, or be aided by a catalyst, heat, or electrolysis. An example of a decomposition reaction would be hydrogen peroxide, H2O2, into oxygen and hydrogen.<\/p>\n Example: Decomposition of hydrogen peroxide: 2H2<\/sub>O2<\/sub>\u00a0\u2192 2H2<\/sub>O + O2<\/sub><\/strong><\/p>\n A precipitation reaction is a reaction in which an aqueous compound reacts to form a solid compound, which may either be suspended in solution or precipitate. Whether it precipitates or remains suspended in the solution depends on the solubility of the ionic compounds.<\/p>\n Example: Salt formation, sodium chloride: 2NaOH(aq)<\/sub>\u00a0+MgCl2(aq)<\/sub>\u00a0\u2192 2NaCl(aq)<\/sub>\u00a0+ Mg(OH)2(s)<\/sub><\/strong><\/p>\n An acid-base reaction or neutralisation reaction is a reaction involving an acid (pH 7, free -OH). Read all the information about acid-base reactions: acid-base reactions<\/a><\/p>\n Example. Hydrochloric acid and caustic soda: NaOH + HCl \u2192 NaCl + H2<\/sub>O<\/strong><\/p>\n In oxidation-reduction reactions, electrons are exchanged, changing the oxidation state of the elements. In oxidation-reduction reactions, one of the elements loses electrons (oxidising) and the other gains them (reducing). They occur in many processes, the best known being the oxidation of a metal, where the metal loses 2 electrons, oxidising. The oxygen on the other hand would gain them, reducing. See all the information about oxidation-reduction reactions<\/a>.<\/p>\n Example. Oxidation of iron: 4Fe + 3O2<\/sub>\u00a0+ 2H2<\/sub>O \u2192 2Fe2<\/sub>O3<\/sub>.H2<\/sub>O<\/strong><\/p>\n You can see a multitude of chemical reactions in the chemistry experiments<\/a> of this website. Here are some examples.<\/p>\nTYPES OF CHEMICAL REACTIONS<\/h2>\n
ADDITION REACTION<\/h3>\n
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COMBUSTION REACTION<\/a><\/h3>\n
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DECOMPOSITION REACTION<\/h3>\n
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PRECIPITATION REACTION<\/h3>\n
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NEUTRALISATION REACTION. ACID-BASE<\/a><\/h3>\n
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OXIDATION-REDUCTION REACTION<\/a><\/h3>\n
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EXAMPLES OF CHEMICAL REACTIONS<\/h2>\n
Sugar Carbonisation with Sulphuric Acid<\/a><\/h3><\/div>\n\n<\/strong> This experiment is a very striking experiment where you can see a sugar combustion reaction, produced by the dehydration of sugar through the action of sulphuric acid. <\/div>\n\n<\/div>\n
Producing Hydrogen, H2, with Aluminium and HCl<\/a><\/h3><\/div>\n\n<\/strong> An exhibition-only experiment where hydrogen gas can be produced by mixing an acid with metal. Be very careful with hydrogen.<\/div>\n\n<\/div>\n
Decomposition Reaction: Oxygenated Water Decomposition<\/a><\/h3><\/div>\n\n<\/strong> In this experiment we can see the rapid and violent decomposition of hydrogen peroxide into oxygen and water.<\/div>\n\n<\/div>\n