Results and Observations
Data Table 1.0: The Solubility Chart Attained from the Results from Part One of the Experiment to Determine the Solubility of the Eleven Cations with Seven Anions
The table shows the solubility of the compounds in water of each cation and anion when reacted together. This solubility chart was then used to determine the Unknown solution (Sample 2).
Data Table 1.1: The Results Attained from the testing of each of the Anions with the Unknown Contaminant
This chart clearly shows that the solubility results attained coincide with the solubility of the Aluminum ion solution with its Anion solution counterparts. In the Solubility Chart of Part One, the Aluminum ion solution was soluble with Acetate, Bromide, Chloride, Phosphate and Sulphate. The Aluminum ion solution was insoluble with only Carbonate and Hydroxide ions.
Conclusion:
From the results attained from Part One and Part Two, it was concluded that the unknown contaminant in Sample Two was a solution of Aluminum ions in the form of Aluminum Nitrate.
Dissolved Aluminum Ions in the Water Systems: What You Need to Know
Aluminum is one of Earth’s most abundant metal that is readily available almost anywhere. Aluminum is very light and silver-white in appearance that is very applicable. Aluminum is a very reactive metal that can easily form oxide and mineral compounds that can be extracted from nature. Aluminum also can bond with water molecules in a hydrated molecule in it’s ionic Al3+ state that is the ionic solution, Al(H2O)63+. However, in its ionic solution form it may be environmentally damaging as it cannot be destroyed by the environment and its various compounds may easily dissolve with water and contaminate the river and lake systems. Therefore, aluminum must be taken care of as a useful but also a dangerous contaminant.
Aluminum exists in water and foods in low concentrations. Aluminum also exists in the air and pharmaceuticals, but in lower concentrations. Since aluminum is generally non-toxic, the average human population ingests approximately a minimum of 30-50 milligrams of aluminum daily and as high as 7 grams a day without severe harmful affects. Even though such high amounts are ingested, but less than 1% from food and less than 5% from water is actually absorbed by the body. Different concentrations of aluminum are found in food, water in air. Levels of aluminum found is0.005-0.18 μg/m³ in air, 0.1 mg/L (100 μg/L) in general water systems and a variety of concentrations in foods and medications. Aluminum with concentrations usually greater than 0.05-0.2 mg/L in drinking water and 15 mg/m³ in air is deemed dangerous and not safe. In the short term, aluminum is not usually harmful to humans. Industry workers who breathe in aluminum dusts or fumes may suffer from respiratory disorders and have decreased performances in tests that measure nervous system functionality. Research has shown that the affects of aluminum usually causes nervous damages and may cause some allergies and rashes. In the long term, aluminum may cause diseases such as Alzheimer’s where patients with Alzheimer's and patients with kidney damage are susceptible to aluminum toxicities as the kidneys may not remove them properly. It is also said that aluminum may aid in causing other nervous and memory diseases such as Parkinson’s and Lou Gehrig’s diseases. Therefore, exceeding safe concentrations of aluminum in water, air and food is harmful for the human body in the long term with chronic nervous and brain diseases as well as lung diseases.
There are many methods of removing dissolved aluminum ions from water. The exchange of ions is one method that is often utilized. In this method, the unwanted ion is exchanged with a more acceptable ion that has the same type of charge (positive or negative). The ion exchange is carried out by the use of insoluble resins that exchanges its ion with the unwanted ion in the contaminated water. If a cation is to be removed a cationic resin is introduced to the water contamination, if an anion is to be removed an anionic resin is introduced to the water. As for the aluminum, it may exist in an acidic state where a cationic resin must be introduced and if the aluminum is in an alkaline state, then an anionic resin must be introduced where in both cases the resin reacts with the aluminum to produce a very insoluble aluminum hydroxide that can be removed. Another method used is the reverse osmosis method. Firstly, osmosis is the process where water moves through a semi-permeable material from an area of high concentration of water to an area of lower concentration. In the reverse osmosis process, the water is forced from the lower concentration of water which has a higher concentration of solutes to a higher concentration of water. This leaves the solutes in it place while the water is removed. In this process the aluminum solutes will be left behind and can be then easily collected. Another process is the sedimentation process where the dissolved particles in the contaminated water is coagulated or collected by other charged particles to make a solid insoluble substance. Then the water is in a suspension and can be left till all the particles is pull by gravity to the bottom or perhaps by centrifugal force. The solutes may then be collected and disposed of. Aluminum ions in the same way can be coagulated by a resin and then the process of sedimentation can be carried out to dispose of it. These are a few of the many methods of removing contaminants such as dissolved aluminum in drinking water that may be used to purify drinking water.
Perhaps the best method is a combination of two methods. The ion exchange system is more efficient as it directly targets the unwanted contaminants and chemically bonds with it to form insoluble material which may be later disposed of. The combination of the sedimentation process may be applied here as a centrifuge may be used to separate all the aluminum. The reverse osmosis process may also be used for smaller household applications, but the equipment is rather expensive and regular maintenance is required. Therefore, the use of ion exchange in a large scale process in water treatment plants is much more economical as large volumes may be treated. However, the combination of two or more methods would be the most accurate as there is a possibility of some contaminants to remain which may be further treated by the second or third method to fully dispose of it. The reverse osmosis is also a relatively good procedure as it can process large quantities of water. However, this method is rather inefficient as many solutes may stay dissolved with the water. This method is also very slow. Thus the use of the ion exchange is the best method as the chemical reactions will create a fast process that can rid the water solution of contaminants.
The procedure used for this report somewhat reflects the coagulation and ion exchange method as the unknown contaminant was identified through solubility means. The unknown solution was first reacted with the Lead ion solution as Lead ion was only soluble with Acetate and insoluble with the rest. This allowed the experiment to be more efficient as tests for the anions could be omitted; this lead to the experimentation of the five cations with the anions to determine the unknown contaminant. The unknown solution was tested with each of the seven anions and the results of the solubility were recorded. One by one the different solubility of each substance was narrowed down to Aluminum. In the Solubility Chart of Part One, the Aluminum ion solution was soluble with Acetate, Bromide, Chloride, Phosphate and Sulphate. The Aluminum ion solution was insoluble with only Carbonate and Hydroxide ions. This clearly showed that the unknown contaminant was Aluminum as the solubility of the unknown contaminant coincided with that of the Aluminum ion solutions.
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