You will need
- - the tubes;
- - tube refrigerator;
- - acetic acid;
- - isopentenyl alcohol;
- - sulfuric acid;
- - sodium hydroxide;
- - iron (III) chloride.
The main feature by which we can determine that the tank is acetic acid, is a characteristic smell of vinegar. To smell, open the flask and make over it a few translational movements of air palm to him. In any case it is impossible to smell volatile liquid, leaning over the container, as this may cause burns of the mucous membranes of the respiratory tract.
All compounds of the class of acids are composed of hydrogen atoms which in aqueous solution to cause acidic properties. Therefore, this substance can be identified using indicators. To do this, take 4 test tubes, pour in each 1 ml of acid and dip them in the indicators (hcl, if they are in the form of solutions). Litmus in acidic medium turns red phenolphthalein color does not change, and methyl orange turns pink-red. 4 tube drop universal indicator, which will be in the solution purple-red. Compare color on a scale, which is included in each box and you will see that it corresponds to an acidic environment.
Spend a reaction to the presence of acetate ion. To do this, take the test tube, pour into it 2 ml of diluted acetic acid, add 1 ml of sodium hydroxide. Get the soluble salt is sodium acetate. Now add to the mixture a few drops of solution of ferric chloride (III) will be a red color. Heat the mixture, then the reaction of hydrolysis will fall a brown sediment. This indicates the presence of acetate ions.
Take the tube, put 2 ml of the test substance add 2 ml isopentanol alcohol. Hcl in a mixture of 1 ml of concentrated sulfuric acid. Close the vial with a tube-fridge and heat the mixture. As a result of interaction there is a pleasant smell of pears due to the formation of the ester.
Advice 2: How to recognize acetic acid
Acetic acid - an indispensable thing in the kitchen. It is used in everyday cooking and for marinades and other delicious things. Some women use it to cleanse the instrument from scale and other economic purposes. To recognize acetic acid is very simple, and to mix it does not work.
Smell - the characteristic difference of acetic acid. It is very sharp and Shiba nose. Don't sniff the bottle with a concentrated vinegar close, bring it in 10-15 cm from the nose. If you are close you can smell fumes coming from the liquid, can burn the respiratory tract and problems will be very much. Try not to drip and the skin will burn.
Acetic acid burn. Pour some liquid into a little bowl and put a match, but be careful you can get burned. Combustion is about the same as the regular alcohol. As it evaporates it ceases. If ignition did not happen, you have either Apple cider vinegar or some other liquid or dilute acid.
Distinctive sour taste speaks for itself. But don't try acid directly from the bottle, you can get severe burns of the esophagus. Pour a teaspoon into a glass and dilute at least 20 parts clean water. Then can try, you should feel the sour taste and sharp smell. In diluted form it is used for making various sauces.
Unfortunately, the home does not carry out any experiments for a more precise definition of the substance. Therefore, other experiments leave for professional technicians. And, of course, do not drink the substance inside if you are in doubt. Acetic acid is very cheap, so better buy a new one than you'd get poisoned unknown composition.
When performing work, observe the safety rules.