This is a lab report on Lead Detection and Toxicity essays

This is a lab report on Lead Detection and Toxicity essays Objective: To detect lead in samples that are at least 1% lead. Materials and Methods/Procedures: 0.5 ml of 6M nitric acid was placed in a test tube, 1.0 g of sample paint chips were added, and the test tube was placed in a beaker of boiling water for 15-20 minutes to dissolve the lead. 10-20 ml of acetic acid was placed on pottery, the pottery was allowed to stand for an hour, the solution was poured into a test tube, which was then placed in a beaker of boiling water for 5-10 minutes. The test tubes were carefully removed and 7-8 ml of fresh 1% sodium sulfite was added to neutralize additional acid. The samples were allowed to cool, the precipitate was allowed to settled ,and a couple of drops of 0.1 M potassium iodine were added to the samples. A raw egg was separated, the white was placed in a beaker, 10 drops of the white were placed in a watch glass, 1 ml (20 drops) of the lead acetate solution was applied, and results recorded. Three people collected 1 ml of saliva in clean test tubes, the saliva was combined in a 25 ml graduated cylinder, the test tubes were rinsed with 5 ml of pH 7 buffer solution, poured into the graduated cylinder with the saliva, enough pH7 buffer was added until the volume was 25 ml, and the mixture was stirred well. Five clean test tubes were labeled, 5 ml of the saliva solution was added to tubes #2-5, while 5 ml of pH 7 buffer was placed in tube #1. 1 ml of the lead acetate solution was added to tube #3-5, and observed for a reaction after 10 minutes, while 1ml of pH buffer was added to tubes #1, #2 and #4. Next, 10 ml of 1% starch solution was added to tubes #1, #4, and #5, and observed after 10 minutes, while 10 ml of distilled water was added to tubes #2 and #3. 5 ml of iodine solution was added to all 5 tubes, and after 15 seconds, the reactions were observed and recorded, and the solutions were ...