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.
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.
Howrad C, D. L. (2001). The Science and Ethics of Water Fluoridation. Journal of Canadian Dental Association, 67(10), 578-580.
Cyclic Voltammetry is an electrochemical method used to study electrically active species. The basic theory behind cyclic voltammetry is that the species being studied undergoes excitation viva a potential. The potential is cycled between two points. Cyclic voltammetry can be used to study kinetics, mechanisms, synthesis, and quantitative analysis. In the following experiment, cyclic voltammetry will be used to study the concentration of acetaminophen in children’s pain reliever. The analysis of the elixir concentration was found to be 28.1 mg/L; given that the specified concentration was 32 mg/L. The percent error of the analysis was found to be 12.1 %.
Warning labels kill me. Have you ever read a label, and it has several deadly side effects, and you're like so what’s makes you think I would even buy this? Why would you even sell this? That’s how I feel about toothpaste. If you read the box toothpaste comes in it's, a warning stating not to swallow and if swallowed call poison control. How extreme for something so commonly used. This is due to the potentially dangerous chemicals. Triclosan, SLS (sodium lauryl sulfate) artificial sweeteners, fluoride, propylene glycol, (DEA) diethanolamine, microbeads and the list can go on an on. Your mouth one of the most absorbent places on your body. So toothpaste doesn’t have to be swallowed for you to be affected. The chemicals pass through the lining
In part A, a strong acid, HCl, was added to the solution. HCl is a strong acid because it completely dissociates in a solution, therefore, it is highly reactive. The negative Cl- ions reacted with the positive metal cations in the
Dental carries is one of the most common oral diseases in the world, and it often goes untreated due to the expense of treatment. According to the World Health Organization (WHO) 60 to 90 percent of school aged children throughout the world suffer from untreated dental carries. Ethnic minorities, the poor, the elderly, and those who are mentally and/or physically disabled are other disparities who also suffer from untreated dental caries (Alcorn & Rogo; 2012). Looking for a way to solve the epidemic of dental caries by providing affordable treatment, silver diamine fluoride (SDF), also known as the “silver fluoride bullet,” was created. Claiming to be both affordable and effective, SDF could be the answer to low cost carries treatment the world has been searching for. The purpose of this paper is to research the efficacy of silver diamine fluoride in comparison to sodium fluoride varnish. Our PICO question is: In a patient with dentinal caries, will the use of silver diamine fluoride compared to sodium fluoride varnish, be more effective at arresting caries?
The experiment, focuses on the effects of acidic drinks on teeth. In this experiment, the scientist is trying to answer which liquids; Arnold Palmer, Coffee, Coca Cola, V8 Splash Tropical Blend, and crest pro-health toothpaste, affect your tooth enamel the most. The Independent Variable are four ounces of each liquid, and the dependent variable is the staining of teeth. The Constants are the toothpaste, toothbrush, the amount of time the eggs stay in the liquid, and the type of eggs used. The units used while measuring the effect of liquids on teeth is ounces.
In conclusion, its recommended that patients brush two-three times a day two minutes long to insure that most of the bacteria is removed from the teeth,gums, and tongue also. Flossing after every meal should also be done regularly because of left foods that get stuck between the teeth. There are many kinds of toothpaste, but not all contain fluorine. Its important that you chose on that does have fluorine because it rebuild tooth enamel and strengthen the tooth too.
Depending on where the fluoride is applied, it can cause different effects. 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;
...the of the world has rejected fluoride and said it was ineffective to the body. Over 94% of the world’s population drinks unfluoridated water (12 Reasons). In Europe, only five out of 48 countries fluoridate, and European health officials have cited medical, effectiveness, and ethical concerns with it (12 Reasons). The people in Portland, Oregon and other countries that don't fluoridate could do other things to prevent tooth decay. Fluoridation is not a way to reduce the high cavity rates in the cities that have fluoridated their waters for a long time. In the city of Portland, To help protect childrens teeth, they should increase the access to dental care. “The Portland Metro Area untreated cavity rates are 21% which is below the average 29% by having better access to dental care and prevention Portland, Oregon could have a lower cavity rates by 2020” (12 Reasons)
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.
With regards to Part B, once the initial two steps of this step were conducted, K2CrO4 was added. This reagent served to help identify whether Ca2+ or Ba2+ was present based on solubility and the presence of precipitate. On the principle of solubility, since the anion CrO42- forms mostly insoluble ionic compounds in water with most cations, Ca2+, could be identified due to that specific cation being one of the few exceptions.9 As a
Brushing your teeth twice a day only cleans twenty-five percent of the mouth at a time. It is for this reason why dentist recommend a healthy fluoride solution to be included into your daily brushing routine; this mouthwash solution will help flush away any food remnants and harmful bacteria from the hard to reach crevasses in the mouth. If this step is skipped it can lead to the formation of dental caries and gum disease, which can lead to worse things if they are not taken care of. To help stress the importance of dental hygiene, Listerine, which is a mouth wash company, released an advertisement for their cool mint flavored antiseptic mouthwash in the hopes of getting non-mouthwash users to jump on the Listerine mouthwash band wagon to proper
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- ...
In this experiment three different equations were used and they are the Stoichiometry of Titration Reaction, Converting mL to L, and Calculating the Molarity of NaOH and HCl (Lab Guide pg. 142 and 143).