The goal of this laboratory experiment was to determine the identity of an unknown ionic compound, unknown sample 3, through the substance’s chemical properties and reactivity. This compound was discovered in a landfill and we needed to know as much information as we can about how the chemical will behave in different situations so that the city will not be negatively affected by the chemical.2 Thus, we first needed to identify the unknown substance, determine some of its chemical properties and reactivity, and also its synthesis.1 To accomplish this goal, we carried out five tests, the conductivity, solubility, cation, and anion tests because they revealed the identity of unknown sample 3.3 In addition, we carried out five reactions, reacting
…show more content…
We needed to perform a solubility test, a cation test, an anion test, and a conductivity test.
In order to find the solubility of the unknown, we needed to have a set amount of the unknown salt, and then add measured amounts of water to determine the minimum amount needed to completely dissolve the salt.
The cation test told whether the unknown contained barium, calcium, potassium, sodium, strontium, lithium, copper, or magnesium. Given a chart of the colors that each burn, lit the unknown on fire with a bunsen burner and compared the flame color with the colors in the chart.
In order to identify the anion, we needed to perform four anion reactions: chloride, sulfate, nitrate, and carbonate. To identify a chloride, equal amounts of the unknown solution, 6M HNO3, and AgNO3 are mixed together and if a white precipitate is formed, the test is positive. To identify a sulfate, equal amounts of the unknown, 6M HCl, and BaCl2 are mixed, and the presence of white precipitate yields positive results. To identify a nitrate, mix 1 mL of the unknown with 3 mL of H2SO4 and cool the solution. Then add 2 mL of FeSO4, if a brown ring forms between the two solutions then the test is positive for a nitrate anion. To identify a carbonate, add 6M HCl drop by drop to the unknown solution. Effervescing, or bubbling, indicates a positive test …show more content…
After the reaction was carried out, the precipitate was separated by vacuum filtration, dried in the oven and weighed. The mass in grams of the expected precipitate when we started with five milligrams of potassium chloride should be similar to the mass of the precipitate we weight after it has been dried. If they are the same, this will help us confirm the identity of the reactants (the unknown sample 3) as well as its chemical properties and
We needed to perform a solubility test, a cation test, an anion test, and a conductivity test.
In order to find the solubility of the unknown, we needed to have a set amount of the unknown salt, and then add measured amounts of water to determine the minimum amount needed to completely dissolve the salt.
The cation test told whether the unknown contained barium, calcium, potassium, sodium, strontium, lithium, copper, or magnesium. Given a chart of the colors that each burn, lit the unknown on fire with a bunsen burner and compared the flame color with the colors in the chart.
In order to identify the anion, we needed to perform four anion reactions: chloride, sulfate, nitrate, and carbonate. To identify a chloride, equal amounts of the unknown solution, 6M HNO3, and AgNO3 are mixed together and if a white precipitate is formed, the test is positive. To identify a sulfate, equal amounts of the unknown, 6M HCl, and BaCl2 are mixed, and the presence of white precipitate yields positive results. To identify a nitrate, mix 1 mL of the unknown with 3 mL of H2SO4 and cool the solution. Then add 2 mL of FeSO4, if a brown ring forms between the two solutions then the test is positive for a nitrate anion. To identify a carbonate, add 6M HCl drop by drop to the unknown solution. Effervescing, or bubbling, indicates a positive test …show more content…
After the reaction was carried out, the precipitate was separated by vacuum filtration, dried in the oven and weighed. The mass in grams of the expected precipitate when we started with five milligrams of potassium chloride should be similar to the mass of the precipitate we weight after it has been dried. If they are the same, this will help us confirm the identity of the reactants (the unknown sample 3) as well as its chemical properties and