08 5月 代码代写：化学实验
The compound identified is KNO3. It is perfectly soluble in water as the first test for solubility in water with 0.1 mg of the compound revealed. Solubility was established at 0.5g/10ml at 25C. The basic physical property of KNO3 is its solubility nature in water. It is soluble in water and in glycerol and is partially soluble in alcohol.Secondly, the PH test was conducted to check for its acidic or basic properties. The test was conducted by use of a PH test strip. The PH test strip will show PH<7 for compounds that are acidic and would show PH>7 for compounds that are basic. In the case of the unidentified compound, it was established that the PH of the dissolved powder is around 7 and this shows a neutral compound. KNO3 has a pH of about 7.In conducting, the flame test, it was identified that the unknown compound contains a potassium cation, because in the flame test, the compound burned purple in color. Only three substances could burn purple in colors which are KCl, K2SO4, and KNO3. Based on the solubility identified of the compound it was established that the compound that dissolves at 0.5g/10ml at 25C with a pH of about 7. The cation in the powder identified was potassium as established in the flame test.
In the second set of experiments, the compound was compared to similar other compounds. Firstly, a test for CO3 was conducted. In the test, 0.1M Hcl was added to the solution and it was identified that the reaction did not fizz so there was no CO3 in the compound. Secondly, a test for Cl was conducted and in it the absence of halide ions was established. Finally, the test for KNO3 was conducted and it was identified that a brown ring was formed at the junction of FeSO4 and the H2SO4 mixed with the compound. Here we faced an issue because firstly the brown ring did not appear. Since all other tests were negative, and there was no white precipitate in the last test, negating the Cl ion, we redid the brown ring test. Same amount of reactance was used, and we compared the tube with rung to another with distilled water in order to find out the difference in darkness and we established KNO3 as the unknown compound. The cation is K by flame test and the anion is NO3 by the nitrate test was hence established.