Flame Test Lab Report

Introduction In order to create a compound, there must be two or more atoms that bind together. These atoms may be made up of different elements, or some may be the same. There are two main ways that atoms bind together- covalently and ionically. In a covalent bond, two non-metals of similar electro negativities come together to share electrons with each other. These electrons come from the outer-valence shells, and are shared in a way so that both electrons can have satisfactory shells, following the octet rule, where the shells are filled and most stable, like the configuration of a noble gas. Ionic bonds are found between two molecules, where one of the molecule gives electrons, whereas the other molecule receives them. This results in …show more content…
These tests are conducted to test for the existence of a chose cation or anion in a compound, and for the most part will only identify whether or not a single cation or anion exists in the compound, except for the flame test. In the flame test, a nichrome wire is dipped into the unknown compound aqueous solution (compound dissolved in H2O). Then, the dipped end of the wire is then held over the Bunsen burner briefly. If a different color of flame is emitted besides the Bunsen burner flame color, then the respective color correlates the existence of a specific cation in the compound- brick orange yields Ca2+, pink yields K+, yellow yields Na+, and green yields NH4+. If the color of the flame does not change, then the test is inconclusive, and no cation is determined from the test, only the nonexistence of the conclusive cations is determined. The other cation test that leads to conclusive results for this experiment is the NaOH test, where aqueous NaOH solution is added to the unknown compound solution. If precipitate forms, the cation can be either Ca2+ or Mg2+. This precipitate would be due to the fact that either of the two cations combines with 2OH- to create a solid product Ca(OH)2 or Mg(OH)2. For the anions, there are several tests that could be used in this experiment, given the list of unknown compounds. The AgNO3 test adds AgNO3 solution to the unknown compound solution, testing to see if the anion Cl- exists in the unknown compound. This is determined because AgCl- (s) is formed in the reaction, which is a precipitate. Another anion test is the BaCl2 test, which concludes if the anion SO4 is found in the compound, which is concluded by a precipitate formed between the reaction of BaCl2 (aq) and the unknown compound solution. Finally, another anion solution is the HCl test, which creates CO2 bubbles when the HCl solution is combined with the