The objective of this experiment is to familiarise with back titration for the determination of calcium carbonate in toothpaste and to determine the percentage of CaCO3 in toothpaste. For this experiment, an excess of HCl was added to a weighed quantity of toothpaste containing calcium carbonate. Back titration is used in this case instead of direct or forward titration as calcium carbonate is insoluble. From the two repeated back titrations that I’ve done, I’ve got an average of 23.73% of calcium carbonate in the toothpaste that I’ve tested. That is fairly near to the desired percentage of abrasive that a toothpaste should contain, which is 10-70% but preferably 20%, and with that I conclude that this experiment was a success.
Calcium Carbonate,
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It is what contributes to the cleaning power of toothpastes as it gives it the gritty texture that it has. Generally, abrasives take up to 50% of toothpastes and when used in excess will cause enamel erosion. Fluorides are also present in toothpastes to prevent cavities. A large variety of toothpastes also contain surfactants as a foaming agent, antibacterial agents, flavourants and colourants for consumer appeal and last but not least, …show more content…
They are different in a way that for direct titration, the acid is titrated directly with the base. While in back titration, the acid is added in excess and after it has reacted with the analyte, the unreacted acid is then back titrated with a known concentration of base. However, titration is not suitable for use under some circumstances and in those circumstances is when one will use back titration instead. One of which is when one of the reagents is an insoluble salt, like in this case, Calcium Carbonate. As calcium carbonate is not soluble, it cannot be dissolved into aqueous form to be pipetted into the conical flask for titration, hence, back titration is more
Improper nutrition and misbalance in our body may be the causes for tooth decay. Always pay attention to your nutrition when your teeth are considered, instead of choosing fluoride or dentistry. Our health can also be in danger when fluoride is used, even though the main reason for using fluoride is to make the teeth stronger. According to a recent study, mental disabilities are often made more difficult with the usage of fluoride. Among fluoride, mercury and arsenic are also dangerous in cases of autism
Fluoride is a trace of nutrients that occurs naturally in water and foods (Wilson). Fluoride has been a problem in the US for quite some time now. And as time goes along, it gets more worse. The only way to fight this problem off is to use less fluoride in our daily lives. This is something everyone should know about because it is getting to the point where it is affecting people's health. The question is, is fluoride being overused in the US? Many people are getting little benefits by the naturally occurring fluoride, plus they are getting more fluoride from the dentist office. There is only a certain amount of fluoride you should intake per day, and these days those numbers are higher than they should be. Fluoride is shown that is it being overused in the US by health issues, chemical intake, and children concerns.
Investigating How the Concentration of Hydrochloric Acid Affects the Rate of Reaction with Calcium Carbonate
No study has been shown to require fluoride, it’s not an essential nutrient. There are many studies, however, that show that fluoride can interfere with important organs such as the kidney. Fluoride added to our waters would also add other toxics that we may not know about. “The CDC admits that 43% of fluoridation chemicals tested contain arsenic, 2% contain lead and 3% contain copper” (12 Reasons). How is that supposed to help our bodies or decrease tooth decay?
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.
H = -443.08 This value is for 2.51g of calcium carbonate, not 100.1g, which is its molecular weight. Therefore: H =
Wiener, R. Constance, Richard J. Crout, and Michael A. Wiener. "Toothpaste use by children, oral
Determining the Concentration Of Limewater Solution Aim: The aim of this experiment is it to find out the concentration of Limewater by performing a titration with hydrochloric acid which has concentration exactly 2.00M.. What is required for me is that I have to design my own experiment and chose the right and appropriate apparatus and equipment. I will be provided with 250cm3 of limewater, which has been made to which contains approximately 1g/dm3 of calcium Hydroxide. This hypothesis from www.studentcentral.co.uk We were also give Hydrochloric acid (HCl) with a concentration of 2.00 mol/dm3 normal laboratory apparatus was also given and so was an indicator.
As the reaction was taking place, the water in the measuring cylinder was being displaced – indicating that the calcium carbonate (in the form of marble chips) was displacing the hydrogen in the hydrochloric acid.
The amount of hydrochloric acid. 3. The concentration of the hydrochloric acid. 4. The surface area of the calcium carbonate.
Acid-Base Titration I. Abstract The purpose of the laboratory experiment was to determine equivalence. points, pKa, and pKb points for a strong acid, HCl, titrated with a. strong base, NaOH using a drop by drop approach in order to determine. completely accurate data. The data for this laboratory experiment is as follows.
I picked the science experiment elephant toothpaste this year, because it seems interesting and fun. It is also a way to test if the removal of oxygen in these experiments will actually work. I have four different experiments. Two out of the four experiments I am testing, is to see if there is a different reaction time and size between yeast and potassium permanganate and the percentage of the hydrogen peroxide. My third and fourth are tests of elephant toothpaste is to see if adding cornstarch has a color reaction to the potassium iodide to make it look like it is “glowing”, or if the yeast and fluorescent dye will make it look “glowing”. I think the elephant toothpaste that uses 50% hydrogen peroxide and potassium permanganate will have the
Investigate how the concentration of hydrochloric acid effects the rate at which it reacts with calcium carbonate
Titration is a technological process in which a solution, known as a titrant, is slowly and carefully added from a burrette into a fixed volume of another solution (known as the sample). In an acid-base titration an acid neutralizes a base or vice versa. This process is maintained untill the reaction between the titrant and the sample (acid and the base) is judged to be complete. The reaction is judged to be complete when the endpoint is reached. An endpoint in a titration analysis is referred to as the point at which no more titrant is added due to an observable colour change of an indicator. Indicators can be used to find an endpoint because they change colour when the pH of a solution changes and an endpoint in a titration is an empirical approximation of the equivalence point, which is the point of major pH change in the titration sample due to the fact that equal chemical amounts of reactants have been combined at that point. All indicators have a pH range, which is the range of pH values at which the colour of the indicator changes. Thus
Lime-soda ash is used to remove the carbonate hardness by precipitation. It does not completely remove the hardness however it is effective in reducing it. It is effective if used to soften temporary hardness. To remove the calcium bicarbonate from the water slaked lime is used. By reacting with the calcium bicarbonate it forms a soluble calcium carbonate, which is then removed by filtering. However a restriction of using lime-soda ash is that it will not work on a lab scale experiment. “An additional deterrent to home use of the lime-soda ash treatment is the size of the equipment necessary, together with the high cost of this method of treatment.” (Lime-Soda Ash Water Treatment Method)