# 0001g use the recordings to determine the mass of the

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0.0001g. Use the recordings to determine the mass of the coin. Repeat these steps two more times for the second and third trial. After obtaining three recordings of the mass of the coin, determine the average mass of the coin and the standard deviation. II.25 mL Volumetric PipetStore distilled water in a 250 mL beaker and place a thermometer to measure its temperature to the nearest 0.01 ºC. Using the table provided in the lab manual, determine the density of the water within the 250 mL beaker based off of its temperature. Obtain a clean 150 mL beaker and record its tare weight to the nearest 0.0001g with the analytical balance. Obtain a pipet and clean the internal surfaces by drawing a few milliliters of distilled water and rotating the pipet so that the water rinses all sides. Discard the rinse solution in the drain. Pipet 25 mL of water into the 150 mL beaker and reweigh the beaker with the added water on the analytical balance. Use this weight as the tare value for the second trial and pipet another 25 mL portion of water into the 150 mL beaker. Record its weight and use that new weight as another tare value for the third trial. Use a third 25 mL portion and record the weight. Use the chart provided in the lab manual to determine the tolerance.
III.50 mL BuretObtain a clean 100 mL volumetric flask and use the analytical balance to weigh it to the nearest 0.0001g. Assemble the buret apparatus by mounting the buret onto a buret stand and fill the buret with distilled water. Ensure that the buret is vertical, the buret tip is filled, and that there are no air bubbles within the stopcock. Place the 100 mL volumetric flask underneath the buret tip and open the stopcock to allow the meniscus to descend a few millimeters. Then open the stopcock again and allow ~10 mL of water to flow into the flask. Record how much milliliters were released to the nearest 0.01 mL. Weigh the receiver and water on the analytical balance. There is no need to empty the receiver for the next trials. Continue to add another ~10 mL portion of water, record how much milliliters were released to the nearest 0.01 mL and weigh again. Add a third portion of ~10 mL portion of water, record the mL and weigh the receiver and water again.
Results:Table 1: Analytical BalanceTrial 1Trial 2Trial 3Mass of weighing paper0.2312g0.2314g0.2312gMass of doing with the paper2.7479g2.7478g2.7472gMass of a coin2.5167g2.5164g2.5160gAverage mass of a coin and STD2.5164g ± 0.00035Table 2: 25 mL Volumetric PipetTemperature of water: 21.5 ºCDensity of water: 0.997910 g/mLVolume of water deliveredTare weight of a 150 mL beakerTare weight of a 150 mL beaker + 25.00 mL waterMass of 25.00 mL of waterCalculated volume of waterToleranceTrial 125.00 mL67.6002g92.3331g24.7329g24.7847mL0.03