The list of many perfumery and cosmetics includes glycerin which makes favorable impact on skin. These are various cream, ointments, detergents. Glycerin in medical, food and chemical industry is not less demanded. Represents transparent liquid without characteristic visual signs. How to define glycerin if, for example, the label from a bottle is lost?
It is required to you
- - test tubes;
- - glycerin;
- - alkali (hydroxide of sodium or potassium);
- - sulfate of copper (II).
Instruction
1. Glycerin is an organic matter which belongs to the class of polyatomic alcohols, in particular to triatomic. It means that it incorporates three hydroxyl groups. On the physical properties glycerin has viscosity and has no smell. Received the name for sweet taste. The word "glikos" is translated as sweet therefore from here and its name – glycerin.
2. For definition of glycerin it is enough to carry out high-quality reaction which will authentically indicate existence of the defined connection in a bottle. For this purpose use freshly cooked solution of hydroxide of copper (II) which with glycerin gives dissolution of a deposit, and solution gets beautiful blue coloring.
3. Take a test tube, pour in it 2 ml of solution of sulfate of copper (II) then gradually add solution of sodium hydroxide or potassium (alkali). As a result of reaction you will observe loss of a deposit of dark blue-light blue color due to formation of hydroxide of copper (II).
4. In other test tube pour 2 ml of glycerin, dilute it 4 ml of the distilled water, close a test tube a stopper and stir up for better hashing. To a freshly cooked deposit of hydroxide of copper (II) carefully flow glycerin solution, close a test tube a stopper and carefully shake up the received mix.
5. The deposit is dissolved practically at once, and as a result of reaction solution of saturated bright blue color is formed that occurs due to formation of complex connection of the glitserat of copper (II). It is also the simplest high-quality reaction confirming availability of glycerin.