As the water flows down and passes over a packing material possessing a large air-liquid inter phase, the volatile organic compounds (VOC) are transferred from the water to the air. It is effective in removing organic as well as inorganic contaminants including hydrogen sulfide. Distillation In this technology, water is heated until it turns to steam, which is then condensed as distilled pure water, free of most dissolved or any solid contaminants including bacteria and viruses. Because distilled water is free of all minerals, it may not be ideal for drinking. Ion Exchange This is a process is used commonly for water softening, by which ions that are dissolved in water are transferred to, and held by, a solid material or exchange resin.
Reverse osmosis is a process which is used in the purification of drinking water that uses a semi-permeable membrane or porous membrane to remove, ions, molecules and large particles from the water by means of applying pressure which overcomes the osmotic pressure. Reverse osmosis can remove many types of bacteria from water. Reverse osmosis results in a way that the solute is retained on the side of membrane which is pressurized and the pure solvent (water in this case) is allowed to pass. Keep in mind that the membrane should not allow large particles, ion or molecules to pass through the pores of the membrane. As such in normal osmosis process, the solvent moves from an area of higher water potential to an area of low water potential.
The solution is then added with NaOH to neutralize the acidity of the solution. Sodium hydroxide is necessary for neutralization as the reduction of the copper(II) ions will not take place in acidic conditions (with present of excess acids). After that, Benedict’s test is carried out by using Benedict’s reagent and heated. At this state, the solution is dark blue in color. Benedict's reagent is an alkaline solution containing Cu(II) ions, which oxidize the aldehyde to a carboxylic acid.
These impurities have to be eliminated because they will produce unwanted insoluble salts by reacting with alkali and carbon dioxide, thus affecting the quality of the soda ash. Brine purification is carried out when magnesium ions are precipitated as hydroxide with milk of lime (Ca(OH)2) whereas calcium ions are precipitated as carbonate with soda ash (Na2CO3). This process is known as lime-soda treatment. The chemical reactions are as follows: Mg2+ + Ca(OH)2 → Mg(OH)2 + Ca2+ Ca2+ + Na2CO3 → CaCO3 + 2Na+ 2. Limestone burning and lime slaking The limestone (CaCO3) used must contain low concentration of impurities.
The purpose of this experiment was to synthesize a Grignard reagent with 1-bromobutane and homogenized magnesium in anhydrous diethyl ether. This solution was refluxed in a flask connected to condenser and drying tube. As seen in the mechanism, maintaining a dry condition is important to avoid the Grignard reagent from attacking water, which will result in loss of the bromine. It is important to reduce the amount of moisture and water vapors to avoid destroying the Grignard reagent, which is essential to the synthesis of 2-methylhexanol. Hence, a calcium chloride and cotton were filled inside a drying tube.
Leaves containing water-soluble elements were boiled and turned from the solid phase into the liquid phase, boiling water. The calcium carbonate was added to form insoluble calcium salts with the tannins and gallic acid so that after vacuum filtration they would be removed. The sodium chloride salt was added after the vacuum filtration in order to raise the polarity of the water, making less amount of molecules soluble in it. This is because the salt takes the part of the space in water and many compounds become insoluble and are pushed out by the salt. By adding the salt we avoid the situation of getting heavy emulsion when mixing tea with methylene chloride.
While initially it seems as though the organic acid, base, and neutral compounds would never pass into the aqueous layer, the conjugate acid and base of the organic base and acid respectively are soluble in water. The conjugate acid and base were obtained by adding concentrated NaOH for acid or HCl for base, hence altering the pH to a point above or below the compound’s pKa. This created a conjugate acid or base that had a negative or positive charge respectively, and was hence not soluble in ethyl acetate and had to pass into the aqueous layer. It is also essential that the extraction solvent be easily removed. In this case, ethyl acetate has a low boiling point, so it can be evaporated away.
Biodiesel is a product from the transesterification of alcohol and vegetable oils and animal fats. In our experiment, the cooking oil and different volume of methanol are used in biodiesel production. Different amount of sodium hydroxide (NaOH) which also known as lye was added to improves the transesterification reaction rate. Since NaOH which is homogeneous strong bases is not consumed by the transesterification reaction, thus it is not reactant, but catalyst. When the methanol and sodium hydroxide are mix, sodium methoxide also known as sodium methylate is produced.
When washing clothes always use laundry detergents that have low levels of phosphate, as phosphate is a major water pollutant. One more important thing is use water wisely. As we all know water is a vital need for every living organism. Do not keep the tap running when not in use especially. You also can reduce the amount of water you use in washing and bathing.
This step mainly retain iodine in the solution. The process of promptly titrating Sodium thiosulfate (Na2S2O3), a reducing agent, to reduce I2 back to I- is known as the iodometric titration. Iodide ions may get oxidised by the atmosphere if the titration