Why does chlorine react vigorously with water?
Water chlorination is the process of adding chlorine or chlorine compounds such as sodium hypochlorite to water. This method is used to kill bacteria, viruses and other microbes in water. In particular, chlorination is used to prevent the spread of waterborne diseases such as cholera, dysentery, and typhoid.
What is advantage and disadvantage of chlorine?
Chlorination is the process of adding chlorine to drinking water to kill parasites, bacteria, and viruses. Different processes can be used to achieve safe levels of chlorine in drinking water. Using or drinking water with small amounts of chlorine does not cause harmful health effects and provides protection against waterborne disease outbreaks.
Why does the water supply industry use chlorine?
Mar 06, 2018 · It kills bacteria/microbes. Explanation: Chlorine, along with ozone and iodine, are some of the most effective antimicrobial chemicals. In pools, we use chlorine (and sometimes ozone as well) to keep it clear of bacteria and algae growth. In water treatment, its the same idea, but the chorine is removed later because it's toxic to drink.
Why is too much chlorine in pools so dangerous?
Chlorination Chlorination involves adding a measured amount of chlorine to water to produce a residual sufficient to kill bacteria, viruses, and cysts. The killing effect of chlorine depends on the pH of the water, temperature, chlorine level and contact time (i.e., the time the chlorine is in the water before consumption).
What is the purpose of adding chlorine to water during the water treatment process quizlet?
What is the purpose of adding chlorine to water during the water treatment process? Chlorine is added to prevent bacteria from growing in the water.
What is the purpose of adding element to the water during the process of water purification?
Alum removes the heavy stones and other insoluble substances from water . Alum removes the suspended clay particles from water. Alum helps to remove odour from water.
What is the effect of chlorine in water?
Many municipalities add chlorine to their water to help kill harmful organisms such as viruses and bacteria that could make us sick if we ingested them. This disinfecting ability is also why swimming pool facilities add chlorine to their water.
How does chlorine affect pH in drinking water?
When chlorine gas (Cl2) is added to the water (H2O), it hydrolyzes rapidly to produce hypochlorous acid (HOCl) and the hypochlorous acid will then dissociate into hypochlorite ions (OCl-) and hydrogen ions (H+). Because hydrogen ions are produced, the water will become more acidic (the pH of the water will decrease).Jan 23, 2017
What is Alum addition?
Alum when added to water, coagulates the colloidal impurities present in water. These impurities settle down and are removed by decantation or filtration, thus purifying the water.Mar 12, 2022
What is water purification Brainly?
Brainly User. Answer: Water purification is a process of removing unwanted wastes, suspended solids and gases in the water for specific purposes like for drinking water. Water purification can happen through boiling, filtration and if you want to remove all the salts and gases present in water, you perform distillation ...May 17, 2020
What is chlorine in water treatment?
Water chlorination is the process of adding chlorine or chlorine compounds such as sodium hypochlorite to water. This method is used to kill bacteria, viruses and other microbes in water. In particular, chlorination is used to prevent the spread of waterborne diseases such as cholera, dysentery, and typhoid.
What is the role of chlorine in water treatment Mcq?
Explanation: Chlorine has the oxidizing power which oxidizes organic and inorganic impurities present in water and the amount of chlorine, which gets consumed before disinfection is called as chlorine demand.
What is chlorine used for?
Its most important use is as a bleach in the manufacture of paper and cloth, but it is also used to make pesticides (insect killers), rubber, and solvents. Chlorine is used in drinking water and swimming pool water to kill harmful bacteria.
How much chlorine is used in water treatment?
Residual requirements vary, but typical residual goal would be for 0.2 to 1 mg/L. In addition to disinfection, chlorine can be effectively used to oxidize iron, manganese and hydrogen sulfide to facilitate their removal, to reduce color in water, and to aid in such treatment processes as sedimentation and filtration.
What is the process of adding chlorine to water?
Chlorination. Chlorination involves adding a measured amount of chlorine to water to produce a residual sufficient to kill bacteria, viruses, and cysts.
What is the final step in chlorine treatment?
Typically, chlorine is added to public drinking water as the final stage of treatment, often following an upstream filtration step which removes sediment that can tie up chlorine and shield organisms from its effect .
What are the reactions between free chlorine and these acids?
Reactions between free chlorine and these acids may produce a class of compounds called trihalomethanes. Strategies to reduce these in public water supplies include enhanced filtration for better organic removal and use of ammonia together with chlorine to produce chloramines for use in lieu of chlorine.
What is the chemical that is added to water to make trihalomethanes?
Chloramines have longer half-life in the water and are less likely to produce trihalomethanes. Chlorine is typically added to water using chemical feed systems to inject liquid sodium hypochlorite (bleach) solution or added as gaseous chlorine (typical of larger public water treatment plants).
Can chlorine be used in water?
Chlorine cannot be used in most high purity water loops without contaminating the process or interfering with the end use of the water. These systems often rely on ultraviolet disinfection as an alternative to water chlorination.
Does chlorine react with organic compounds?
Unfortunately, chlorine reacts with many organic compounds to form chlorine disinfection by-products that are recognized as potent carcinogens at low levels of concentrations. Such organic compounds include humic and fulvic acids, which derive from rotting vegetation common in surface waters.
What is the purpose of adding chlorine to water?
The main objective of this chlorine addition is to disinfect the water and maintain chlorine residuals that will remain in the water as it travels through the distribution system.
Why is chlorination important in water treatment?
In order to combat waterborne diseases, different disinfection methods are used to inactivate pathogens. Along with other water treatment processes such as coagulation, sedimentation, and filtration, chlorination creates water that is safe for public consumption.
What is the combination of free chorine and hypochlorite?
At lower pH levels, the hypochlorous acid will dominate. The combination of hypochlorous acid and hypochlorite ions makes up what is called ‘free chorine.’. Free chlorine has a high oxidation potential and is a more effective disinfectant than other forms of chlorine, such as chloramines.
What is chlorine breakpoint?
Residual Chlorine, Breakpoint. Any type of chlorine that is added to water during the treatment process will result in the formation of hypochlorous acid (HOCl) and hypochlorite ions (OCl-), which are the main disinfecting compounds in chlorinated water. More detail is provided later on in this fact sheet.
How is calcium hypochlorite made?
Calcium hypochlorite (CaOCl) is made up of the calcium salts of hypochlorous acid. It is produced by dissolving chlorine gas (Cl 2) into a solution of calcium oxide (CaO) and sodium hydroxide (NaOH). Calcium hypochlorite is a white, corrosive solid that comes either in tablet form or as a granular powder. Calcium hypochlorite is very stable, and when packaged properly, large amounts can be purchased and stored until needed. The chemical is very corrosive however, and thus requires proper handling when being used to treat water. Calcium hypochlorite needs to be stored in a dry area and kept away from organic materials. It cannot be stored near wood, cloth or petrol because the combination of calcium hypochlorite and organic material can create enough heat for an explosion. It must also be kept away from moisture because the tablets/granular powder readily adsorb moisture and will form (toxic) chlorine gas as a result. Calcium hypochlorite has a very strong chlorine odour – something that should be kept in mind when placing them in storage.
What happens after chlorine demand is met?
After the breakpoint, any additional chlorine added will result in a free chlorine residual proportional to the amount of chlorine added.
How much calcium hypochlorite is needed for water treatment?
Compared to the 1-16 mg/L required with chlorine gas, only 0.5-5 mg/L of calcium hypochlorite is required. When calcium hypochlorite is added to water, hypochlorite and calcium ions are produced.