Pre-chlorination is found to remove tastes and odors and control biological growth throughout the water treatment system, thus preventing growth in the sedimentation tanks and the filtration media. The water enters at the top and passes through the bed of Zeolite. Boiler efficiency decreases as the valves and condensers of the boilers are choked. Here the chemicals along with the water are heated near about the boiling point of water by exhaust steam. Should not contain nitrates- scale and sludges.

The presence of some dissolved mineral material in drinking water is the reason for the waters characteristic and pleasant taste. The equipment is costly. The water then diffuses out of the cracks, leaving behind hydroxide salts that accumulate when more water evaporates. Revision Intermediate students should be able to track the cause of hardness down to these cations and say that the anions make no difference. Carbonate conditioning, Phosphate conditioning, Calgon conditioning, etc.

Only when all the calcium ions have been precipitated out as scum will the water lather. We use cookies to give you the best experience possible. This process is carried out by using ion exchange resins, which are long chain, cross linked, insoluble organic polymers with a micro process structure. When the cation exchange resin in exhausted, it can be regenerated by passing a solution of dil.

Also, anion exchange units will remove nitrate and fluoride, but cation exchange units will not. This results in overheating and sometimes burning out of these plates and tubes.

Wash the pipette, burette and conical flask with the de-ionised water. Maintaining uniform heat distribution. Retention components at the top and bottom consist of screens, slotted cylinders, or alternative suitable devices with openings smaller than the resin beads to prevent the resin from escaping from the vessel.


The units with volatile gas vents can remove some volatile organic chemicals as well.

Hardness in water, USGS Water Science School

Prevention of the sludge and scale formation can be done by two methods, namely, Internal conditioning method and External conditioning methods. When water containing calcium carbonate is heated, a hard scale is formed that can plug pipes and coat heating elements.

This volume should be subtracted from the other volumes before the relative hardnesses are compared.

chemistry coursework hardness of water

Scales have a thermal conductivity value which is less than that of the bare steel. Internal treatment for silica If silica is present in the feedwater, it tends to precipitate directly as scale at hot spots on the boiler metal and or combines with calcium forming a hard calcium silicate scale.

Hard Water – Chemistry LibreTexts Hardness is defined as the concentrations of calcium and magnesium ions expressed in terms of calcium carbonate. An improvement for this lab would be test o hard water sources rather than just one faucet. The softened water passes through a filtering media ensuring complete removal of the sludge and finally the filtered water flows out through the top. This is permanently hard water.

Make a note of the volumes of soap solution that were needed in each case to produce a lather. Each of us is qualified to a high level in our area of expertise, and we can write you a fully researched, fully referenced complete original answer to your essay question.

Ion exchange or demineralization process chemiatry almost all ions present in the hard water. The reaction between the red indicator-metal complex and the EDTA reagent at the end point can be represented as follows:.


Cation exchange resin is represented as RH2.

This would cause excess EDTA to cuemistry present causing inaccurate results. Water does not come in direct contact with tubes and plates of boilers due to the formation of scales.

chemistry coursework hardness of water

Generating, collecting and testing gases Generating, collecting and testing gasestaking care that the gas carries over no acid spray, whereupon calcium carbonate is soon precipitated. The water courseworkk fed into cylinder-I where all the cations are replaced by RH2 resins. Hard water courseaork dissolved calcium or magnesium salts that react with soap solution to form an insoluble scum that should be seen as a white cloudiness in the tubes: Revision Intermediate students should be able to track the cause of hardness down to these cations and say that the anions make no difference.

In distillation, the water is evaporated, leaving the impurities behind.

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Equipment The ion exchange resin is contained in a vessel with a volume of several cubic feet. The calcium salts responsible for the formation of boiler scale. There are two types: Essay UK – http: This Practical Chemistry resource was developed by the Literature review decision making Foundation and the Royal Society of Chemistry.

This shows that temporarily hard water can be softened coursweork boiling see theory below.