LA MUSIQUE FRANCAIS

“CHEMICAL REACTIONS IN AND AROUND US”

A chemical reaction is any change that occurs in matter. It involves a change from reactant substances to product substances, and the product substances may have physical and chemical properties. Chemical reactions tend to involve the motion of electrons, reading to the formation and braking of chemical bonds. There are some types of chemical reactions like: combustion, synthesis, decomposition, single displacement, double displacement and acid-base. ……………………………………                      The combustion reaction happens when a compound and an oxidant is reacted to produce heat. The synthesis reaction is when two or more chemical species combine to form a complex product. The decomposition reaction it is a complex molecule that breaks down into a new one. The single displacement is when one element trade places from a compound by another element. The double displacement reactions occur when parts of two compounds change place to form two new compounds. And finally the acid-base reaction is when an acid and base react with each other. ……………………………………………………………………                                        Some examples of the chemical reactions are: when cleaning your oven or removing a clog from a drain this is an acid-base reaction; also, the combustion reactions help to release the energy to move our vehicles. The rusting of iron is an example of synthesis reaction; the making of pigments and the removal of salt from water in water treatments is an example of the application of a double reaction.    Chemists use statements called equations to represent the chemical reactions.  To write a chemical equation you should place the reactants on the left side of an equation with an arrow pointing to the substances being formed on the right side of the equation, the products. Example:   ……………………………..........................                          …………               (reactants)  H + O          (products)   …………………………                    When there are more than two products a plus sign separates each one. The reactants and products can exist as solids, liquids and gases; but when it are solve in water then they said that passes to be aqueous.     …………………………..........                     A chemical equation is form by: formulas, symbols(+)(->) (this include coefficients), parenthesis (when there is more than one of an ion or group that is polyatomic) and a sub-index.               ……………………...................…………………….............                                               To balance an equation you can apply the law of conservation of mass to get the same number of atoms of every element in each side of the equation. Balance chemical formulas by placing coefficients in front of them, you may not add subscripts because this will change the formulas. Use (g) for gaseous substances, (s) for solids, (l) for liquids and  (aq) for species in solution in water.                                            Finally, chemical reactions are part of our daily lives. From cooking in the kitchen, to driving a car, these reactions are commonplace.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            [pic 2][pic 1]

“INTOXICATION WITH CO, A SILENT KILLER”                                                                                                                                                                                                 

The carbon monoxide (CO) is a colorless, odorless gas produced by burning material containing carbon and this is also known as the “silent killer”. Carbon monoxide consists of one carbon atom and one oxygen atom, connected by a triple bond that consists of two covalent bonds as well as one dative covalent bond.                  It poisoning can cause brain damage and death. Some properties of the carbon monoxide are: it is sparingly soluble in water, has a melting point of -199degC, a boiling  point of -91.5degC, it is a flammable and highly toxic gas, neutral oxide which burns in air to give carbon oxide and it is a good reducing agent.                CO is a common industrial hazard resulting, but one of the most common sources of exposure in the workplace is the internal combustion engine. From the incomplete burning of natural gas. The carbon monoxide poisoning is the most common type of fatal air poisoning in many countries, it binds to other molecules such as myoglobin and mitochondrial cytochrome oxidase (this is a large trans membrane protein that is found in bacteria and the mitochondrion)             …………………………………….                                                                                                        The carbon monoxide it is connected by a triple bond that consists of two covalent bonds. Paint removers containing methylene chloride also "create" carbon monoxide. The CO is present in small amounts in the atmosphere like, the product of volcanic activity and the man-made fires (burning crop residues, bushfires and sugarcane fire-cleaning).Though methylene chloride does not give off carbon monoxide, the vapors are converted within the body into carbon monoxide. As a result, a person can suffer carbon monoxide poisoning from inhaling methylene chloride vapors.                         The CO poisoning causes mental confusion can rob the heart and brain of oxygen headaches, dizziness, disorientation, nausea and fatigue but sometime is possible to be poisoned without having any symptoms at all. Another consequence is the low levels in the blood. The symptoms depend on the quantity of carbon monoxide that people inhale:                                               10%: no symptoms. 15%: headache. 25%: nausea and serious headache.        30%: symptoms intensify. 45%: unconsciousness. 50+%: death.                                        In other hand, the carbon monoxide also have uses like producing gas or water gas, it is widely used as a fuel in industrial operations; for example, when carbon monoxide is passed over hot iron oxides, the oxides are reduced to metallic iron, while the carbon monoxide is oxidized to carbon dioxide

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