01 Feb Preparation of soluble salt like sodium chloride
Chemistry tuition classes in Miracle Learning Centre are easy to understand and help you in the chemistry tuition application questions. If you do not understand chemistry in school, you must definitely come for chemistry tuition classes at Miracle Learning Centre. Let us learn about the preparation of soluble salt like sodium chloride in this chemistry tuition lesson.
To prepare Group I salts or any sodium, potassium, ammonium salts, we need to use titration. The reagents are acid reacting with an alkali or acid reacting with a soluble carbonate. For example, if we need to prepare sodium chloride, we need to use the titration method. This is because sodium chloride is a soluble salt and it is a Group I salt. To prepare sodium chloride, we need to react hydrochloric acid with sodium hydroxide to form sodium chloride and water. To prepare potassium sulfate, we need to react sulfuric acid with potassium hydroxide to form potassium sulfate and water. The last example would be to prepare potassium nitrate. To prepare potassium nitrate, we react nitric acid with potassium hydroxide to form potassium nitrate and water.
Let us look at the procedures to prepare soluble salt like sodium chloride.
We mentioned above to prepare sodium chloride, we need to react sodium hydroxide with hydrochloric acid. Hence we first rinse the burette with distilled water then with sodium hydroxide. Then we will fill the burette with sodium hydroxide. We will rinse the pipette filler with distilled water then with hydrochloric acid. We then pipette 25cm3 of hydrochloric acid into a conical flask which has been rinsed with distilled water. Add 2 drops of Phenolphthalein in hydrochloric acid and it appears red in colour. We shall now titrate hydrochloric acid against sodium hydroxide. The sodium hydroxide is added 1cm3 at a time. We need to find out when the first drop of sodium hydroxide cause the change from red to colourless. This titration needs to be carry out a few times in order to get an accurate reading of the final titration results. After we get the final results, we need to repeat the experiment without any indicator. The resulting solution is now pure sodium chloride. The pure sodium chloride is obtained by crystallization. The solution is heated to evaporate the excess solvent until a saturated solution is produced. We continue heating the solution to dryness to obtain crystals of sodium chloride.
This example appears easy but many students will be confused and use the incorrect reagents. Regents like sodium and hydrochloric acid is incorrect. Regents like sodium sulfate and hydrochloric acid is incorrect. Regents like sodium nitrate and potassium chloride is incorrect as well. Hence, if you are not entirely clear about preparation of Group I salts, the reagents you use may be incorrect. The rest that follow will be incorrect as well.
Miracle Learning Centre aims to educate students about what how to prepare a soluble salt like sodium chloride. Do come to Miracle Learning Centre for more chemistry tuition lessons to learn more about how to prepare sodium chloride.