Two test tube sizes will be used, 13 x 100 mm and 10 x 75 mm. Do not remove this bottle from the fume hood because it is fuming ammonia which will “stink -up” the lab. The 15M NH3 (concentrated) will be available in lab fume hood. c) Label dropper bottles clearly and put your name and date on the reagent tray.Ġ.5M KOH 6M NaOH 6M NH3 (labeled as NH4OH) b) AVOID SPILLS by transferring the approximate volume wanted to a small beaker. If there are reagents in the bottles in your locker, empty them out and rinse the bottles with distilled water from your wash bottle.įill the dropper bottles with the solutions listed below. Obtain a red plastic tray with six dropper bottles. You may wish to test parts of your scheme on known combinations of ions. Then examine the results to decide how each of the ions could be identified when others are present.
Your observations should include precipitation or no precipitation as well as colors. Record your observations for each test in a table in your notebook. For each set of samples, you will test a known set of standards to see how they react with certain reagents. There will be a maximum of six substances to report in this unknown. In addition, you must look for and report H, + OH, NH3 and NH4 if present. Anions (Group 3): Three groups of anions. The unknown will contain no less than two ions in this group. Cations (Group 2): Ba, Ni, Co, Fe, Zn and Al. The unknown will contain no less than two, no more than four of the ions in this group. Cations (Group 1): Ba, Ag, Hg2, Cu and Zn. There will be three unknowns for you to analyze based on three different groups of ions. You will work out your own scheme for analyzing a mixture containing some combination of a group of ions. In this experiment, you will be required to id entify the ions in an unknown mixture. An example of a quantitative test would be an acid/base titration to determine c oncentration (volumetric analysis). Cation Separation Example.Ĭhemistry 102 Quantitative analysis is a method used to determine exact amount. The separation of ions is easily achiev ed by taking advantage advanta ge of their solubility properties (Flow-Chart 1). Examples of qualitative tests would include ion precipitation reac tions (solubility tests) or chemical reactivity tests. In many cases, qualitative analysis will also involve the separation of ions or compounds in a mixture. Qualitative analysis is analysis is a method used for identification of ions or compounds in a sample.
0 kommentar(er)
