The goal of the lab was to investigate the properties and structure of an unidentified compound that was discovered in a local landfill. The group was called in to help determine the chemical and physical properties of the compound so we can let the people of the town know so it can be taken care of properly with or without further precautions to be taken. Another goal of this project was to devise the synthesis of the unknown compound.
Experimental Design
In order to determine the correct identity of our unknown compound, we first started with a couple preliminary tests, which include physical state and smell. The physical state test inquired a thorough overview of the compound. If our compound has a distinct smell, we can conclude …show more content…
The solvents we used were water, 0.1 M NaOH, 0.1 M HCl, acetone, and toluene. We began by adding a small amount of the compound to five test tubes, and added 2mL of each of the solvents into the test tubes, stirred, observed and recorded the reactions that took place.
We then executed a quantitative solubility test to calculate the solubility of the compound in grams per liter. We began this test my measuring out .062g of compound and 2mL of water and put them into an Erlenmeyer flask. While heating and stirring the flask we add our solution until our compound has completely dissolved. Place a watch glass on top of the flask and allow cooling until the next class. Then filter out the remaining liquid, allow it to dry and then weigh it. With this information we can calculate the solubility of the compound in grams per liter.
A flame test was then performed to determine the cations present in the compound. By placing the nichrome wire in our compounds and putting it into the flame we can analyze the color of the flame to determine which cation is present in our compound. Along with the flame test, came the ammonium test to detect if the cation, ammonium, is present. By adding 1mL of our compound solution and 1mL 6M NaOH, a smell will develop if the ammonium cation is …show more content…
The pH test will confirm if the compound is an acid or base.
After we performed the previous tests, we created five reactions that we knew would react with our predicted compound in a certain way. We came up with one reaction that would result in a white precipitate, and in the other four the compound will not react and only dissolve in the solution. We completed this test for both our known and our unknown and compared results.
Finally, we performed the gravimetrical analysis for our compound, in order to conclusively prove our unknown compound is what we predict. We first find an equation that we know will create a precipitate and dissolve 0.5g of our compound into 4mL of water. We then add the precipitating agent to our compound solution until no more solid seems to precipitate. After allowing the precipitate to settle, put the test tubes into the centrifuge and allow enough time for the precipitate to filter from the solution and form on the bottom. After the centrifuging is complete, pour the remaining liquid out of the tube and scrape the remaining precipitate onto filter paper. Place the filter paper in the oven and allow to dry until the solid crumbles to the touch, and weigh the precipitated compound. With the mass of the precipitated compound and the formula, we can calculate the moles and the mass of the compound present. We can then