Lab Report: Qualitative Analysis
Aim: The aim of this experiment is to identitfy an unknown powder by conducting several experiments to determine the anion and cation of the given salt.
Hypothesis: The unknown salt named “H” could be ferric nitrate ( iron(III)nitrate) since the salt exists as pale violet crystals.
Qualitative Observations: When testing for nitrate ions I saw that the gas given off from the solution turned the red litmus paper blue. This showed the presence of nitrate ions since ammonia gas was given off when aqueous sodium hydroxide and aluminium foil was added and the solution was warmed. I also observed that a red-brown ppt. formed when sodium hydroxide was added to the unknown aqueous solution which showed the presence of iron(III) ions.
Conclusion: The results of the qualitative analysis show that the given unknown salt is composed of nitrate and iron(III) ions. Therefore it can be said that the unknown salt named “H” is iron(III) nitrate. The result matches the hypothesis, as the the unknown salt is found out to be ferric nitrate (the same as iron(III) nitrate). Ferric nitrate exists as pale violet crystals. I took an educated guess and said that the unknown substance could be iron(III) nitrate since their physical qualities match.
Evaluation: The experiment was a complete success. Nothing went wrong since I followed the procedure carefully, step by step. If I were to do this experiment again I would like to identitfy couple of other salts. Other than that I wouldn’t change anything about this experiment.
The letter code of the salt investigated: H (iron(III)nitrate)