Table of Contents
Introduction………………………………………………………………………………. 2
Procedure………………………………………………………………………………… 4
Data………………………………………………………………………………………. 7
Results and Discussion…………………………………………………………………... 9
Conclusion and Opinion………………………………………………………………... 10
References……………………………………………………………………………..... 11
Introduction
Purpose
The purpose of this experiment is to determine the weight percent of fluoride in a toothpaste sample by using a fluoride ion-selective electrode. Using the fluoride ion-selective electrode will offer an introduction to the procedures of potentiometric analysis [2].
By comparing the experimentally determined weight percent of fluoride to the known value listed by the toothpaste manufacturer, the accuracy of this experiment can be assessed. It is important to accurately measure fluoride levels in consumer products because fluoride can be lethal. While small a small amount of fluoride is necessary for healthy bones and teeth, too much fluoride can cause kidney failure and death [2].
Potentiometry
Potentiometric analysis measures potential with a voltmeter, reference electrode, and indicator electrode. There is no net current with these measurements [1].
Fluoride Ion-Selective Electrode
A fluoride ion-selective electrode, or FISE, is a type of indicator electrode. This solid-state type electrode has an ion-selective membrane made of LaF3. The FISE is filled with a solution that contains F- ions. The concentration of this filling solution is higher than that of the sample solution, so F- ions leave the electrode, pass through the membrane, and enter the sample solution. The free energy from this diffusion of F- ions creates the potential that is measured by the voltmeter [1-3]....
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... use to determine the amount of NaCl to add to each solution. This part was difficult because instructions were not very clear. Consequently, a member of my group used incorrect volumes in her equations and added incorrect amounts of NaCl. Because of this, we had to use another lab group’s data.
Improvements
Detailed instructions on the use of the pipette would make
this lab easier. Additionally, an explanation of the ionic strength equation and the determination of NaCl additions would be helpful.
References
1. Barlag, Becky. Class Notes 2013.
2. Barlag, Becky. Lab Manual for Analytical Chemistry I, Fluoride Ion-Selective
Electrodes. Ohio University, 2013.
3. Ion-Selective Electrode: The Measurement of Fluoride Ion Activity in Mouthwash,
Toothpaste, and Drinking Water. University of Conneticut, 1999. http://chemweb.chem.uconn.edu.
At this point the identity of the unknown compound was hypothesized to be calcium nitrate. In order to test this hypothesis, both the unknown compound and known compound were reacted with five different compounds and the results of those reactions were compared. It was important to compare the known and unknown compounds quantitatively as well to ensure that they were indeed the same compound. This was accomplished by reacting them both with a third compound which would produce an insoluble salt that could be filte...
Firstly, an amount of 40.90 g of NaCl was weighed using electronic balance (Adventurer™, Ohaus) and later was placed in a 500 ml beaker. Then, 6.05 g of Tris base, followed by 10.00 g of CTAB and 3.70 g of EDTA were added into the beaker. After that, 400 ml of sterilized distilled water, sdH2O was poured into the beaker to dissolve the substances. Then, the solution was stirred using the magnetic stirrer until the solution become crystal clear for about 3 hours on a hotplate stirrer (Lab Tech® LMS-1003). After the solution become clear, it was cool down to room temperature. Later, the solution was poured into 500 ml sterilized bottle. The bottle then was fully wrapped with aluminium foil to avoid from light. Next, 1 mL of 2-mercaptoethanol-β-mercapto was added into fully covered bottle. Lastly, the volume of the solution in the bottle was added with sdH2O until it reaches 500 ml. The bottle was labelled accordingly and was stored on chemical working bench.
The purpose of this experiment was to test which brand of whitening toothpaste is the most effective. The original hypothesis was that Crest 3D White Advanced Toothpaste be the most effective, while Arm & Hammer Advanced Whitening Toothpaste will be the least successful in whitening the tiles. The hypothesis also stated that the Sensodyne and Colgate brands will be equally as effective, while being more sufficient than Arm & Hammer, but less than Crest. The hypothesis was partially supported as Arm & Hammer was the least effective and Crest was the most. However, Sensodyne was more sufficient than Colgate. This was clearly displayed on the graphs
In the first part of this project, two cation elimination tests and one cation confirmation test were performed. 10 drops of 4 cation solutions: potassium, zinc(II), copper(II)
Few object to the therapeutic use of fluoride to stop tooth decay, but fluoridation, the addition of fluoride to the public water supply, can spark avid controversy. Most dentists, medical groups, and government officials argue that fluoridation is a cheap and risk-free venture that doubles cavity prevention. In contrast, a small minority of dentists and conservative political groups argue that fluoride is a hazardous, poisonous substance that should not be consumed. Some antifluoridationists even claim that fluoridation is an untrustworthy form of socialized medicine. But rather than just attacking fluoridation as socialized medicine, opponents originally claimed that it was a conspiracy to poison or brainwash Americans through the water supply. This theory arose in the 1940s when the scientific community refused to endorse or reject fluoridation, thus allowing the debate to expand into the social sphere. While fluoridation opposition may be subconsciously inspired by naturalism, the social development of fluoridation into a Communist or fascist conspiracy resulted from a conscious effort by conservatives to suppress a growing government.
Fluoride is a mineral derived from a naturally occurring element called fluorine. Fluorine is the 13th most abundant component on Earth, and you'll find it all round us in the air and water. Toothpaste comprises fluoride. While hard line anti-fluoride consumers bypass fluoride-enriched toothpaste, most people use it because it's been shown to help avert cavities. It does so by sustaining your saliva which assists to avert the buildup up the tooth plaque that leads to cavities. It also helps to guard against to decrease of minerals helpful to tooth enamel.
Fluoride added in our waters would also add other toxics that we may not know about. “The CDC admits that that 43% of fluoridation chemicals tested from contain arsenic, 2% contain lead and 3% contain copper” (12 Reasons). How is that supposed to help our bodies or decrease tooth decay? Scientist say, that the level of them are too low to do any damage to our bodies. The Environmental Protection Agency however, states that arsenic and lead have incre...
There are numerous flaws in all the evidences that support fluoride addition to water. Scientists who try to speak against the fluoridation are pressurized to change their findings. Even minute concentrations of fluoride are associated with bone disorders and dental problems. Fluoride also removes the lead coatings of the drinking water pipes due to which toxic concentrations of lead is also present in drinking water.
solution NaOH and finding its pH. The titrant NaOH which is 1M is filled in the burette. Below
Wiener, R. Constance, Richard J. Crout, and Michael A. Wiener. "Toothpaste use by children, oral
A M Helmenstine states that, when applied directly to teeth, ‘Fluoride [interacts] with hydroxyapatite to form a stronger compound that is less-susceptible to acid attack’ 3. The following is an extract from ScienceLine explaining how the fluoride prevents tooth decay. However, on the other hand, if fluorine is digested it has the potential to form hazardous compounds, in particular Hydrofluoric Acid (HF). An example of this is seen below, in a reaction that Sodium Fluoride partakes in with naturally occurring Hydrochloric Acid in the stomach; NaF + HCl → HF + NaCl This acid is known for being highly corrosive and toxic. Furthermo... ...
Flouride application is one of the method to limit the caries development due to poor oral hygiene to eliminate the caries development.
Fluoride to strengthen tooth enamel and remineralize enamel in the early stages of tooth decay.
Introduction: Titration is a common laboratory practices that is involved in quantitative chemical analysis. This process is also called titrimetry or volumetric analysis (since we are dealing with volumes in our analysis). This process is used is used to determine unknown concentration of a solution. This is unknown solution is known as the analyte. The standard solution or known concentrations is called titrant. The titrant and analyte react to determine an accurate concentration of the unknown solution. This is the process that happens in titration. There are many types of titrations like acid-base titrations, redox titration, and gas phase titration, but the most commonly used titration is acid base titration. An acid base titration is used when an acid or base concentration needs to be known (for example this lab is an acid base titration). In the process of acid- ...
There are many uses for new inventions. Edible toothpaste is used in space and in society. For example, in the 1960’s, rocket ships (Apollo 11) were tight and cramped. These rockets could not fit a toilet or a sink in as the whole rocket was filled with mission-related equipment. In space this toothpaste was used so that a toilet or a sink was not needed to brush one’s teeth. As the flights were really long and oral health would become a problem, scientists wanted to solve this problem. These scientists worked with dentists and sought to find a solution. This is how they came up with space paste or also known as ingestible toothpaste. Another useful and innovative toothpaste is made from all-natural ingredients, which makes it a very healthy toothpaste. This toothpaste is called Neonisin. There is an active ingredient in Neonisin and this is “Nisin”. Nisin is a peptide, which is harvested from lactic bacteria found in soy bean curd. In daily life, this toothpaste is used in many families as an alternative toothpaste for children and as a first toothpaste for babies. This is possible ...