Hydrated Crystals HASPI Medical Chemistry Lab Draft

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1 Hydrated Crystals HASPI Medical Chemistry Lab Draft Backround/Introduction Manesiusm In The Body Manesium (M) is a mineral that is present in lare amounts in the human body. It is a very important cofactor in more than 300 chemical reactions that keep the body workin properly, includin but not limited to: Protein synthesis Muscle contraction Brain and nerve function Blood lucose control Blood pressure reulation Enery production Structural development of bones DNA and RNA synthesis Neutralizin stomach acid and peristalsis in the intestines The averae person s body contains about 25 rams of manesium, with 50-60% stored in the bones. People et manesium throuh their diet and levels are larely controlled by the kidneys. On averae, about 120m of manesium is excreted into urine each day. Dietary Intake of Manesium Manesium is widely distributed in plant and animal foods and beveraes. Nuts, seed, whole rains, and veetables like broccoli, squash, and spinach are ood sources of manesium. In eneral, foods that are hih in fiber are hih in manesium. Other sources include dairy products, meats, chocolate, and coffee. Sometimes manesium supplements are needed if manesium levels are too low and are readily available in a variety of forms. Table 1 outlines the Federal Dru Administration s Recommended Dietary Allowances for manesium by ae and ender. Table 1: Recommended Dietary Allowances for Manesium AGE MALE FEMALE PREGNANCY LACTATION Birth 6 months 30 m 30 m 7-12 months 75 m 75 m 1-3 years 80 m 80 m 4-8 years 130 m 130 m 9-13 years 240 m 240 m years 410 m 360 m 400 m 360 m years 400 m 310 m 350 m 310 m years 420 m 320 m 360 m 320 m 51+ years 420 m 320 m Manesiusm and Health Manesium deficiency due to low dietary intake is uncommon but risks include habitually low intake or excessive losses of manesium due to certain health conditions, chronic alcoholism, and/or the use of certain medications. Sins of manesium deficiency can be as mild as a loss of appetite, nausea, vomitin, and fatiue. In more severe cases individuals may experience numbness and tinlin, uncontrolled muscle contractions and cramps, seizures, personality chanes, abnormal heart Hydrated Crystals, HASPI Medical Chemistry Lab DRAFT 1

2 rhythms, and hypocalcaemia or hypokalemia (low levels of calcium and potassium due to a disruption in mineral homeostasis). Research has shown that manesium deficiencies miht be involved in cardiovascular disease, type 2 diabetes, osteoporosis, and miraine headaches. While more well-desined, lare trials are needed for more evidence, some studies suest that manesium supplementation can cause a small decrease in blood pressure amon hypertension patients and reduce the risk of stroke. Likewise, diets with hiher amounts of manesium are associated with sinificantly lower risks of diabetes, osteoporosis, and chronic miraine headaches. Too much manesium is not a bi health risk because properly functionin kidneys eliminate excess amounts in urine. However, hih doses of manesium from dietary supplements or medication can result in diarrhea and abdominal discomfort. Manesium toxicity in the body usually only occurs when individuals consume upwards of 5,000 m/day, which is more than ten times the FDA s recommended daily allowance. Manesiusm in Medications and Treatments Manesium sulfate (MSO 4 ), also known as Epsom Salt, is one of many manesium containin compounds that can be used for medical treatment. Manesium sulfate can be prescribed for many reasons and can be bouht at the local rocery store for a number of home remedies. If taken orally, manesium sulfate holds on to water in the lare intestine, preventin the body from reabsorbin fluids. This will cause the bowels to evacuate and can help someone who has constipation. Manesium also depresses the central nervous system, blockin nerve sinals in the muscle. Soakin in a bathtub of warm water and Epsom Salt can help alleviate body aches and pains. If prescribed by a doctor, other manesium containin compounds can help stop seizures by limitin muscle movements. Manesium can also be used for treatin attention deficit-hyperactivity disorder (ADHD, anxiety, chronic fatiue, Lyme disease, fibromyalia, and if applied topically it can be used to treat infected skin ulcers and speed up wound healin. Review Questions 1. What role(s) does manesium play in the human body? 2. How does the body reulate manesium levels? 3. What types of foods are ood sources of manesium? 4. What is your recommended daily intake of manesium accordin to the FDA? 5. Why do you think the recommended daily allowance of manesium increases for prenant females? 6. Is it possible to have too little/too much manesium in your body? What happens if that happens? 7. Give an example of a manesium containin compound and explain how it can be used for medical purposes. Hydrated Crystals, HASPI Medical Chemistry Lab DRAFT 2

3 Hyrdrated Crystals HASPI Medical Chemistry Lab # A Scenario A water ecule has a stron dipole, which means it has partial chares on either end. This is due to the asymmetric structure of water and the uneven electroneativity between hydroen and water. Because of these partial chares, water is very attracted to ions. Fiure 0: The polarity of water This attraction is the reason that ionic substances dissolve and dissociate in water. The water surrounds the ions so that it can move around in the solution. In some cases, the water and the ions are so stronly attracted that when the water is evaporated from the solution some of the water ecules are trapped within the crystals that form. This happens in specific ratios for the chemicals that form hydrates. In this lab we are oin to work with Manesium Sulfate Hydrate, a crystal made of MSO 4 and water. Your oal is to find the number of water ecules for each manesium sulfate in the system. Removin water from the system requires enery, which makes the removal Fiure 2: MSO4 of water an endothermic reaction. For many hydrates you can merely heat them for a period of time in order to force out the water. Once you have removed the water we call these an anhydrate, a term used for the compound once the water is removed. This also means that if you add water it is an exothermic process, where the enery is released as water is re-interated into the crystalline structure. Materials Safety Goles Bunsen Burner Rin Stand Clay Trianle Forceps Crucible Diital Scale Hydrated Crystals, HASPI Medical Chemistry Lab DRAFT 3

4 Procedure/Directions Your lab team will be ivin tasks, or directions, to perform on the left. Record your questions, observations, or required response to each task on the riht. 1 Task Obtain the necessary materials provided by your instructor. Set up your Bunsen burner, stand, and clay trianle. Response Be sure to keep your work area neat and oranized. Wear safety oles at all times at your work station and secure all lon hair and loose clothin. 2 Find the mass of your crucible and cover. Record your measurement. 3 Find the mass of your crucible, cover, and manesium sulfate sample. Record your measurement. Usin your measurement in step 2, calculate the mass of just your manesium sulfate hydrate sample. Mass of crucible & cover: Mass of crucible, cover & sample: Mass of hydrate sample: 4 Carefully place your crucible, cover and sample on the clay trianle and heat over a Bunsen burner for 10 minutes. Mark the time you start the heatin process and calculate the time you need to remove your sample from the heat. Heat Start Time: Heat End Time: While heatin your sample, you may work on another assinment iven to you by your instructor. Be mindful of you Bunsen burner and work area. 5 Turn off your Bunsen burner and let your crucible, cover, and sample cool down for 20 minutes. Mark the time you turned off the Bunsen burner and the time it is safe to handle the crucible. Coolin Start Time: Coolin End Time: While coolin your sample, you may work on another assinment iven to you by your instructor. Be mindful of you Bunsen burner and work area. 6 Once your crucible is cool enouh to handle, find Mass of crucible, cover & heated sample: Hydrated Crystals, HASPI Medical Chemistry Lab DRAFT 4

5 the mass of the crucible, cover and heated sample. Record your measurement. Since you already know the mass of crucible and cover (step 2), calculate the mass of the heated, anhydrous sample. Mass of crucible & cover: Mass of anhydrous sample: 7 Usin the data you athered in step 3 and step 6, calculate the amount of H 2 O in your sample. Remember to use the correct number of sinificant fiures. Mass of hydrate sample (Step 3): Mass of anhydrous sample (Step 6): Mass of H 2 O: 8 Calculate the es of H 2 O present in your oriinal MSO4 XH2O hydrate sample. Remember to use the correct number of sinificant fiures. 9 Calculate the es of anhydrous MSO 4 present in your sample. Remember to use the correct number of sinificant fiures. 10 Derive an empirical formula (ratio between H 2 O and anhydrous MSO 4 ) for your oriinal hydrated sample. Use the es calculated in steps 8 and 9. This ratio becomes the coefficients in your compound. MSO 4 H 2 O Hydrated Crystals, HASPI Medical Chemistry Lab DRAFT 5

6 11 Calculate the percent of water in a perfect sample of manesium sulfate. Use the formula: MSO 4 7H 2 O 12 Calculate the percent of water in the manesium sulfate sample from your lab results. Use the formula you calculated in step 10 based on your e ratio) 13 Calculate your percent of error based on results of steps 11 and 12. Use your final% answers and plu in to % error formula 100 Analysis & Interpretation Summarize your data into the followin data table: Measurements Manesium Sulfate Crucible, cover & sample Hydrated sample Crucible, cover & heated sample Anhydrous sample H 2 0 in sample Moles of H 2 0 in sample Moles of anhydrous sample Empirical Formula MSO 4 H 2 O Hydrated Crystals, HASPI Medical Chemistry Lab DRAFT 6

7 Analysis Questions 1. Explain why water is hihly attracted to ions. 2. In this lab, you turned Manesium Sulfate Hydrate into an anhydrous compound. Is this an exothermic or endothermic reaction? Explain your answer. 3. The method used in this experiment to find the percentae of water in the hydrated crystals is not suitable for all hydrates. Give at least two reasons why this may be so. 4. Why should the mass of the crucible be measured immediately after the crucible cools and not later? 5. Discuss 2 possible reasons for your observed percent error. 6. Your lab procedures were reproduced for a different hydrate sample, Copper II Sulfate, CuSO 4 H 2 O. If the followin values were taken before and after the sample was heated, fill in the remainder of the data table to find the amount (in es) of H 2 O and Copper II Sulfate in in your sample. Measurements Crucible, cover & sample Hydrated sample Copper II Sulfate Crucible, cover & heated sample Anhydrous sample H 2 0 in sample Moles of H 2 0 in sample Moles of anhydrous sample Empirical Formula CuSO 4 H 2 O Hydrated Crystals, HASPI Medical Chemistry Lab DRAFT 7