Acetic, or ethanoic acid is an organic compound of a class of monobasic carbonic acids. Derivatives of this substance are called acetates. In the divorced look acid is available practically in each kitchen as table 6% or 9% of vinegar. It is used for preparation of various salads, marinades, confectionery and also at conservation of vegetables.
It is required to you
- - test tubes;
- - tube fridge;
- - indicators;
- - acetic acid;
- - isopentsilt alcohol;
- - sulfuric acid;
- - sodium hydroxide;
- - chloride of iron (III).
Instruction
1. The main sign by which it is possible to determine that in capacity there is acetic acid is the characteristic smell of vinegar. To feel a smell, open a bottle and make over it several progress of air a palm to yourself. It is impossible to smell flying liquid at all, having low bent over the capacity as it can lead to a burn of mucous membranes of airways.
2. All connections of a class of acids incorporate hydrogen atoms which in water solution and cause sour properties. Therefore this substance can be determined by indicators. For this purpose take 4 test tubes, pour in everyone 1 ml of acid and lower in them indicators (flow, if they in the form of solutions). Litmus in acidic environment becomes red, phenolphthalein does not change the coloring, and methyl orange gains saturated rose-red color. In the 4th test tube lower the universal indicator which will become in solution in violet-red color. Compare coloring on a scale which is available in each packing and you will see that it corresponds to acidic environment.
3. Carry out reaction to existence acetate ion. For this purpose take a test tube, pour in it 2 ml of the diluted acetic acid, add 1 ml of sodium hydroxide. Soluble salt - sodium acetate will turn out. Now add several drops of solution of chloride of iron (III) to the received mix – red coloring will appear. Heat mix then as a result of reaction of hydrolysis the brown deposit will drop out. It demonstrates about existence acetate ions.
4. Take a test tube, place in it 2 ml of the studied substance, add 2 ml of isopentsilt alcohol. Flow 1 ml of the concentrated sulfuric acid in mix. Close a test tube a tube fridge and heat mix. As a result of interaction the pleasant smell of pear due to formation of ester appears.