Recognition of salts of sodium is quite specific task which in everyday life is hardly useful. But knowledge and abilities such can be necessary on a practical training or when performing laboratory trials. In spite of the fact that the same metal is a part of chemical compounds, there are high-quality reactions by means of which it is possible to distinguish sodium salts.
It is required to you
- The calcinated delay in an eyelet on the end, sodium salts (table salt), a spirit-lamp or a torch, a stick
Instruction
1. It is known that when burning various substances, the flame gets various coloring. It occurs thanks to certain chemical elements which are a part of connections. For example, the flame because of calcium has a brick-red shade, and potassium at combustion gives violet color which is well visible through cobalt glass. And if to calcinate a usual copper delay on a flame, then fire will turn out beautiful green color. How to distinguish sodium salts in such variety of the "burning" chemical compounds?
2. Prepare three solutions of salts of sodium for a research: sodium chloride, sulfate of sodium and carbonate of sodium. That is the same metal – sodium and only the acid remains at them different is a part of all three salts. All offered salts of sodium are well soluble in water, at the same time their solutions are transparent, so, on appearance are identical. But it will not prevent to define sodium if it is correct to make laboratory trial.
3. Now take a copper delay 20-30 cm long, on the one hand make a small eyelet with a diameter of 0.5-0.7 mm. Then light a spirit-lamp which can be both on liquid alcohol, and with use of dry fuel.
4. Bring the received eyelet in a flame and calcinate it. The beautiful green flame as copper gives such coloring will be observed. After the eyelet becomes covered by a black raid and will cease to burn in green color, lower it in one of solutions of salts of sodium and again take over a flame. Beautiful yellow coloring will be observed until solution of salt does not evaporate. The same will occur also other salts, namely yellow color of a flame.
5. Other way recognition of salts of sodium assumes use not of solutions, and solids. It is enough to make sure of it, having taken usual table salt which represents sodium chloride. For this purpose moisten a stick with water and dip in salt that grains stuck and bring in a torch flame (it is possible also rings). Also you will see that the flame becomes intensive-yellow color.