Abstract: The purpose of this experiment was to identify given Unknown White Compound by conducting various test and learning how to use lab techniques. Tests that are used during this experiment were a flame test, ion test, pH test, and conductivity test. The results drawn from these tests confirmed the identity of the Unknown White Compound to be sodium acetate (NaC2H3O2) because there were no presence of ions and sodium has a strong persistent orange color. The compound then will be synthesized with the compounds Na2CO3 and HC2H3O2 to find percent yield.
Determining the Identity of an Unknown White Compound Maxwell Yurs Group Member: E.B. Floersch, Alexander Medina, and Masih Horri College Science and Engineering University of Minnesota, Minneapolis October 12, 2014 The experiments that were completed were used to determine the identity of an unknown white compound to allow for proper disposal. These experiments included flame tests, pH tests, and conductivity tests. After each was completed, it was found that the identity of the white compound was Sodium Nitrate.
The scientists will conduct the experiment by taking four cups of water one that is just salt mixed with water, another that is just water, a third cup that is just ice water and finally a forth cup that is vinegar and water mixed. After that the scientists will drop one Alka-Seltzer tablet into each cup and see how long it takes for it to completely dissolve. The scientists will conduct these three times for
Materials: Equipment and materials used in this experiment were: unknown metal samples (2) 100 mL graduated cylinder electronic balance tap water wire screening weigh dish (Dixie cup) Methods: The mass of five different amounts of an unknown metal sample was determined using an electronic balance and a weigh dish. The volume of these five different amounts was determined using a 100 mL graduated cylinder and tap water through the method of water displacement. The water was poured into the sink using the wire screening to separate the metal from the water. This process was repeated for the second metal sample.
After 15 minutes, the cheesecloth was removed from the mason jar, and massed on the balance. A plastic 669 mL container was used as a weigh boat. The balance was zeroed and the cheesecloth was placed on the balance. The mass was recorded in a notebook.
After setting up the computer 50 mL of cold water was measured into a test tube. After measuring 50 mL the water was measured for initial mass. The test tube was positioned 1.5 to 2.0 cm above the food holder and food sample.
Fifteen milliliters of water were once again placed in the chamber for another three minutes, and the final results were
This heating and cooling was repeated until there was very little (less than 0.0010 grams) fluctuation in numbers. Vial one had a start weight of 14.7681 and an end weight of 15.4098, meaning the mass of the water was 0.4658. Vial 2 had a start weight of 14.7451 and an end weight of 15.3833, meaning the mass of the water in this sample was 0.4633. The mass of the water was found by subtracting the mass of the vial with the hydrate (the start weight) from the mass after the final heating (the final weight). To then find the percent water divide the water mass by the hydrate mass and multiply by 100 since the number is a percent.
The items that were massed were the evaporating dish, watch glass, and NaCO3. The materials were massed once before and once after being heated in the drying oven. The mass of the evaporating Dish before was 46.57 g; while after being heating was 60.15 g. The mass of the watch glass before was 57.97 g and after was 48.75g. There were two masses taken for the substance NaHCO3- one with the evaporating dish and one without, subtracted out after the lab was concluded. The mass of the substance with the dish was 48.79 g before and 62.33 g after; meanwhile, the mass of the substance without the dish was 2.22 g before and 2.18 g after. The mass of the NaHCO3 had changed after the reaction occurred along with after it was placed on the hot plate and being in the drying oven.
Our procedure for part two of the lab affected the mass much less than part one because we had found an adequate way to collect most of the gas in the flask. Unlike part one where some of it went
In this lab, we were trying to figure out the density of unknown metals. We determined the density at the end by first measuring the mass of the metal on a scale, then using water displacement, finding the volume of the metal. First, we decided to use metal B. We took out one piece of the metal and measured the mass by placing it on the scale. Then, we filled up the graduated cylinder with exactly 20 mL of water.
3. Using the 100 cm3 measuring cylinder, measure 100 ml of water and pour it into the Styrofoam cup with the lid. Record the new mass displayed. 4. Place the Styrofoam cup with the lid into the beaker.
The weight of the precipitate was used to determine the mass of
This experiment has to be carried out carefully
Zero the scale. Pour one of the 4 substances into the plastic container “h”. Record mass of first substance.
