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Keeping this cookie enabled helps us to improve our website. As a disinfectant in water, chlorine is more than three times as effective against Escherichia coli as bromine , and more than six times as effective as iodine. It is often impractical to store and use poisonous chlorine gas for water treatment, so alternative methods of adding chlorine are used.
These include hypochlorite solutions, which gradually release chlorine into the water, and compounds like sodium dichloro-s-triazinetrione dihydrate or anhydrous , sometimes referred to as "dichlor", and trichloro-s-triazinetrione , sometimes referred to as "trichlor".
These compounds are stable while solid and may be used in powdered, granular, or tablet form. When added in small amounts to pool water or industrial water systems, the chlorine atoms hydrolyze from the rest of the molecule forming hypochlorous acid HOCl , which acts as a general biocide, killing germs, micro-organisms, algae, and so on. The breathalyzer is a redox reaction. When the potassium dichromate reacts with ethanol it loses an oxygen atom gets reduced , going from the orange dichromate to the green chromium sulfate.
At the same time dichromate is being reduced, ethanol gains an oxygen atom gets oxidized , forming acetic acid. The sulfuric acid helps to remove the ethanol from the exhaled air into the test solution and also provides the necessary acidic conditions. Hydrogen peroxide can be used for the sterilization of various surfaces, [58] including surgical tools [59] and may be deployed as a vapour VHP for room sterilization.
Hydrogen peroxide is seen as an environmentally safe alternative to chlorine -based bleaches, as it degrades to form oxygen and water and it is generally recognized as safe as an antimicrobial agent by the U.
Historically hydrogen peroxide was used for disinfecting wounds, partly because of its low cost and prompt availability compared to other antiseptics. It is now thought to inhibit healing and to induce scarring because it destroys newly formed skin cells.
H 2 O 2 can induce healing, and only if not repeatedly applied. Diluted H 2 O 2 between 1. The chemical's bleaching property lends its name to the phrase " peroxide blonde ". It can be. Almost all applications of potassium permanganate KMnO 4 exploit its oxidizing properties. Potassium permanganate is used for a number of skin conditions. Benzoyl peroxide BPO is a medication and industrial chemical. Sodium hypochlorite is most often encountered as a pale greenish-yellow dilute solution commonly known as liquid bleach or simply bleach , a household chemical widely used since the 18th century as a disinfectant or a bleaching agent.
The compound in solution is unstable and easily decomposes, liberating chlorine , which is the active principle of such products. Indeed, sodium hypochlorite is the oldest and still most important chlorine-based bleach.
While sodium hypochlorite is non-toxic, its corrosive properties, common availability, and reaction products make it a significant safety risk. In particular, mixing liquid bleach with other cleaning products, such as acids or ammonia , may produce toxic fumes. Austin State University with contributing authors. Learning Objectives Know the occurrence and properties of oxygen. Know reactions involving oxygen as an oxidizing agent. Oxygen: Occurrence and Properties By mass, oxygen is the third- most abundant element in the universe, after hydrogen and helium.
Though oxidation is a natural process involving the loss of electrons, when it occurs too often within cells, the over-oxidated cell can be chemically damaged which can cause problems for the organism and which has been linked to several diseases such as cancer, hypertension, and rheumatoid arthritis to name a few.
Free radicals are simply atoms or groups of atoms with unpaired electrons in the valence shell. Why is this so deadly? Most atoms want to attain a stable outer shell.
In order to be stable, free radicals must obtain an electron so that the electrons are paired. Because the outer shell contains unpaired electrons, free radicals are extremely reactive. In our bodies, free radicals will oxidize the nearest molecule taking the needed electron. The oxidized molecule will then become a free radical, beginning a chain reaction.
This chain reaction will continue eventually resulting in the disruption of a living cell. Free radicals can attack lipids fats , proteins, carbohydrates, and DNA. However, DNA is a prime target. DNA and free radical interactions usually result in mutations that adversely affect the cell cycle and potentially lead to malignancy. In fact, researchers believe this is how many forms of cancer arise. Antioxidants are substances that protect the body from damaging oxidation reactions by slowing or halting oxidation in organic cells.
The antioxidants can safely interact with free radicals and prevent the damage of vital molecules. Antioxidants are able to neutralize the free radical chain reaction by reacting with the free radical. In order to stop the chain reaction, the antioxidant donates the needed electron. The antioxidants also do not become a free radical by donating the electron, safely ending the chain reaction.
The antioxidants are able to do this because they are stable in either form. Plants are the most important source of antioxidants. This is one of the reasons why a diet rich in fruits and vegetables is essential for good health. They are used by the plant as their own antioxidants, and they continue to work as antioxidants in our bodies after we eat them. These compounds are often colored, hence we are encouraged to eat a variety of fruit and vegetables of different colors.
So the blue of blueberries, the purple of blackberries, plums and grapes, the orange of carrots and squashes, the red of strawberries, raspberries, tomatoes, and red cabbage are all beneficial antioxidants, which should be an essential part of our healthy eating. Other good food sources of antioxidants are broccoli, spinach, kale, peas, garlic, avocado, white meat, tuna, lentils, beans, nuts, seeds, onions seafood,.
Billions of dollars are spent worldwide each year to prevent and clean up after a special family of redox reactions - the corrosion of metals. Iron and steel which is mostly iron can be oxidized to metallic ions by water and oxygen in the environment.
Oxygen is reduced by the reaction to either the oxide or hydroxide ion. The corrosion is described by these equations:. When iron corrodes, a coating rust forms from loosely packed particles which water and air can penetrate continuing the attack on the metal underneath. Silver corrodes tarnishes when it comes in contact with foods, such as eggs, that are rich in sulfur compounds or trace quantities of H2S or SO2 in the atmosphere.
Corrosion occurs even more easily in the presence of salts or acids. Oxidizing and reducing agents are key terms used in describing the reactants in redox reactions that transfer electrons between reactants to form products. This page discusses what defines an oxidizing or reducing agent, how to determine an oxidizing and reducing agent in a chemical reaction, and the importance of this concept in real world applications.
An oxidizing agent , or oxidant , gains electrons and is reduced in a chemical reaction. Also known as the electron acceptor, the oxidizing agent is normally in one of its higher possible oxidation states because it will gain electrons and be reduced. Examples of oxidizing agents include halogens, potassium nitrate, and nitric acid. A reducing agent, or reductant , loses electrons and is oxidized in a chemical reaction. A reducing agent is typically in one of its lower possible oxidation states, and is known as the electron donor.
A reducing agent is oxidized, because it loses electrons in the redox reaction. Examples of reducing agents include the earth metals, formic acid, and sulfite compounds. To help eliminate confusion, there is a mnemonic device to help determine oxidizing and reducing agents.
Identify the oxidizing agent and the reducing agent in the following redox reaction:.
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