![]() You could add some interest to which salts are used, and which salts are formed. Using cut-out card labels: ‘sodium’, ‘magnesium’, ‘carbonate’ and ‘sulfate’ for students to move around will help many of them grasp the idea of ‘swapping partners’. It needs to be approached carefully, probably by group or whole class discussion. Suggesting the name of the salt left in solution is not easy for students at this stage. Magnesium sulfate + sodium carbonate → magnesium carbonate + sodium sulfate The experiment can be made more exciting visually by making a coloured salt such as copper(II) carbonate in this case the chemical hazard level is slightly higher, since copper(II) carbonate is HARMFUL.īecause this is intended as a first introduction, the interpretation should be restricted to developing the word equation as a summary of what has happened: This experiment is intended as a first introduction to this phenomenon for 11–14 year olds, as well as to practical filtration techniques. The formation of precipitates on mixing two solutions is met frequently in chemistry. There are no significant hazards in this experiment, except for the risk of broken glass if a flask is knocked over. The apparatus set-up for the experiment making magnesium carbonate Teaching notes Label with your name(s) and leave in a warm place, safe from interference, until it has dried completely (a few hours). Remove the wet filter paper carefully from the funnel and place on a clean dry paper towel.If the solution is not clear, and white cloudiness remains in it, you will need to repeat the filtration. A clear solution should collect in the flask. ![]() Only pour in enough solution at a time to leave the solution level 1 cm below the rim of the filter paper. Swirl the reaction mixture gently, and pour a little at a time into the filter paper in the funnel.Fold the filter paper to fit the filter funnel, and put it in place.Place the filter funnel in the neck of another conical flask.Mix 25 cm 3 of magnesium sulfate solution and 25 cm 3 of sodium carbonate solution in a conical flask.Magnesium carbonate, 3MgCO 3.Mg(OH) 2.3H 2O(s) – see CLEAPSS Hazcard HC059b.Magnesium sulfate solution, MgSO 4(aq) – see CLEAPSS Hazcard HC059b.Sodium carbonate solution, Na 2CO 3(aq) – see CLEAPSS Hazcard HC095a and CLEAPSS Recipe Book RB080.All containers used for these solutions should be labelled. If the reagent solutions can be distributed in pre-measured quantities, waste is reduced and lesson organisation is easier.Read our standard health and safety guidance.Magnesium sulfate solution, 0.5 M, 25 cm 3.Sodium carbonate solution, 0.5 M, 25 cm 3.The cheapest grade of filter paper is okay for this experiment. The size of filter paper, when folded, should match the funnel size. Polythene filter funnels are safer and cheaper than glass funnels.Filter papers (size suited to funnels used).Filter funnel (65 mm diameter or similar, note 1).This experiment is therefore suitable as a class experiment for most classes. Even these can be minimised by the use of polythene filter funnels. So the few other safety issues are essentially restricted to safe handling of glassware. Sodium carbonate in dilute solution is weakly alkaline. If the solutions can be provided in pre-measured 25 cm 3 quantities in labelled containers, distribution of chemicals and control of quantities can be easily managed, and the practical work can begin without delay. It should take no more than 20 minutes to the point at which the wet product can be set aside to dry. This is a short standard class experiment. In this experiment the soluble salts are magnesium sulfate and sodium carbonate, and the insoluble salt formed is magnesium carbonate, which can be filtered, dried and collected. RSC Yusuf Hamied Inspirational Science Programme.Introductory maths for higher education. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |