Calcium Supplement Lab Writeup 71435k

Calcium Supplement Sanat Malhotra November 5th, 2014 CHEM 1611-116 Lab partners: Hanna Dickerson, Mark Restrepo, Benjamin Ghaemmaghami Abstract Calcium is required in our everyday diet to maintain a multitude of bodily functions and keep us healthy, which is why the consequences of the lack of calcium may be severe. Supplements can be taken in different forms such as ingested in solid form, or in liquid form. Calcium carbonate, one of the most common substances that naturally contain calcium, is often chalky and difficult to swallow when ingested in its solid form. This cannot be prevented, as calcium carbonate does not dissolve in water. This experiment was designed to fix this problem, targeted towards the elderly, who may have trouble swallowing solid supplements, which can make them more prone to ailments that have to do with lack of calcium, such as osteoporosis. Osteoporosis occurs when bones are weak, and brittle, which is why the elderly are more prone to contracting it. The supplement needs to go down easily, and effectively to accommodate the weakened system of elderly people. By carefully crafting this experiment, calcium carbonate can be reacted with multiple substances that allows calcium to be soluble, resulting in a solution that can be easily ingested, while providing the same amount of calcium (RDA standard), and with minimal toxins. 1

Introduction Calcium is required in our body to maintain the strength of bones and teeth, hence ing the skeletal structure and function.1 Deficiency of calcium, either by diet or genetics can cause multiple ailments such as osteoporosis, a disease in which bones become fragile and weak. This can lead to a higher chance of fracturing bones, and more recovery time. Genetics, age, smoking, and other factors affect the likelihood of contracting osteoporosis. The Recommended Dietary Allowance (RDA) ranges from 700 mg to 1300 mg for calcium from ages 10 – 71+ years.2 This is something we have to take into when performing the experiment and creating the supplement, as the amount ingested should be little enough that it’s realistic to ingest everyday, but also contain the right amount of calcium needed for the respective age group it is intended for. The form of calcium the experiment uses is calcium carbonate, a cheap source of calcium, but hard to ingest as it is insoluble and has an unappealing texture. By reacting this solid with an acid, the calcium ions can be separated as the hydrogen ions bond to the carbonate ions, creating carbonic acid, leaving the calcium ions still in 1 U.S. Department of Health and Human Services. Bone Health and Osteoporosis: A Report of the Surgeon General. Rockville, MD: U.S. Department of Health and Human Services, Office of the Surgeon General, 2004. www.surgeongeneral.gov/library 2 Committee to Review Dietary Reference Intakes for Vitamin D and Calcium, Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: National Academy Press, 2010.

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the water. The lower the pH, the higher the solubility of the calcium, however, the pH has to be in an acceptable range for it to be safe for consumption. This process to safety will require titrating the newly made solution with sodium hydroxide, a strong base, increasing the pH to the safe level. If the pH is too high or too low after titration, it can be adjusted using more acid or base, as needed. An EBT indicator along with an EDTA solution containing magnesium is introduced in the titration, which will indicate when the pH is in the safe range, which translates to the buffered solution (pH 10). This will ultimately help find the concentration of calcium in the solution, hence making it easier to find the optimal dosage and amount needed per day. Experimental For the experiment 3.00 grams of calcium carbonate was taken with 100 mL of deionized water. The calcium carbonate does not dissolve so it is simply placed in the water. 6 mL of 1.00 M HCl was added next to the solution and stirred to ensure maximum surface area for the reaction. Another 3 mL of 1.00 M NaOH was added, to raise the pH of the acidic solution. If the pH is out of the safe range (4 -10), it is further titrated to the right level. If the solution is acidic, NaOH is added through a burette into the solution to neutralize it, raising the pH. If the solution is basic, HCl is added through the same process, being carefully measured, until it is neutralized to the safe pH. The 3

pH is tested with the indicator and EDTA. The EBT3 (Eriochrome Black T) indicator will not work unless the pH is in the specified range, while the EDTA is used to measure the concentration of calcium ions in the solution. This can later be used to calculate the amount needed for the correct dosage as prescribed by the RDA. Results and Discussion Evaluation plays an integral role in scientific experiments. Accuracy may be lost due to the random and systematic error. If analog, make sure you are reading the right scale, and calculating with appropriate units with double-checks. Chemically, in order to make calcium carbonate soluble, the following equation was used: CaCO3(s) + 2 HCl(aq)

H2O(l) + CO2(g) + CaCl2(aq)

followed by a reaction with NaOH… 2 NaOH (aq) + CaCl2(aq )

2 NaCl(aq) + Ca(OH)2(aq)

Calculations:

3 D. Spurlock. (1999-2014) Determination of Water Hardness By Complexometric Titration Class Notes. Retrieved from http://homepages.ius.edu/DSPURLOC/c121/week13.htm [Accessed 12/01/2014]

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First, the calculations concluded the amount of moles of calcium ions is in the solution. These calculations also show that 0.162 L of this solution is necessary to consume per day to receive the correct amount of calcium in your diet. This is only 162 mL which is practical and reasonable enough to be included in an everyday diet. When tested, the pH strip showed a pH of 8, which is in the acceptable range, however being a little off neutral, on the basic side. An improvement can be making sure the pH is completely neutral, which would allow more solubility of the calcium, as well as a safer pH to drink. Safety is ensured by using eye goggles when handling the corrosive chemicals such as NaOH and HCl. Some limitations of our experiment include materials and time given, as the calcium could’ve been sourced from something that is more soluble. An error that occurred during the performance of the experiment was that too much Na OH was added and this inhibited the calcium hydroxide from dissolving in the solution. Titration measurements could’ve been done more accurately to results, and calculations could have been repeated to double check claims. By measuring the initial volume of 5

the chemical added from the burette and subtracting that from the final, we can obtain the volume required to neutralize the solution. Then by using stoichiometric ratios, we calculate the equation, concentration, and other necessary measurements for the experiment. The final solution is minimally toxic, as shown by the pH of 8, which is highly neutral. This was done by neutralizing the solution with the acid/base needed. The change in pH is caused by added hydrogen ions or hydroxide ions to the solution. When the concentration of hydrogen ions is high, the pH is highly acidic, and when hydroxide is added, it reacts with the present hydrogen ions to form water, diluting the solution, and decreasing the concentration of hydrogen ions. The resulting solution checked off all the criteria of the optimal solution, being clear, falling within the RDA and safe pH level. With a high dosage, harm can be inflicted on your body, therefore the recommended dosage is what is required in the resulting solution. Percentage yield can be analyzed and optimized by using minimizing errors that may be caused in non-controlled environments. Conclusion Calcium supplements are an effective way of getting the required amount of calcium in your body. We successfully created a calcium supplement that was clear, minimally toxic, that contained the RDA for calcium, and had a pH of 8. The experiment can be furthered by testing it on individuals to see how it reacts in the body, as well as 6

modifying the taste of the solution, should there be an unappealing taste. A simpler, more direct way of synthesizing a calcium supplement can also be investigated, now that the foundation and process behind it is known and tested.

On my honor, as a UVa student, I pledge that I have neither given nor received aid on this assignment. x__________________________

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