Study of amino acid properties

Topic of laboratory lesson №15

Study of amino acid properties

Purpose of the work: familiarization with the main chemical properties of amino acids

Reagents and equipment: 1% - glycine solution, 0.2% - methylhyzyl solution, Copper (II) oxide, 0.2 n sodium hydroxide, 2H. hydrochloric acid, concentrated solution of sodium hydroxide, nitric acid (r=1,4г/мл), crystal and 10% solution of copper(II) sulfate , sodium acetate, 1% - solution of iron(Sh) chloride, 40% - formaldehyde solution, 10% - lead nitrate solution.

Tools: test tubes, alcohol lamp.

1-experience. Amphoteric property of glycine. In 0.5 ml of glycine solution, drop 1 drop of methyl red. Another 2 drops of formaldehyde solution are injected into the test tube.

2-experience. Reaction of amino acids with iron(Sh) chloride.

Drop 2 drops of iron(Sh) chloride per 1 ml of glycine solution. What does this reaction prove? You need to write the reaction equation

3-experience. Reaction with copper salts.

In a test tube, you need to pour 1 ml of glycine solution and put copper cuporos and sodium acetate crystals in it. It is necessary to mention the phenomenon seen. It is necessary to write the equations of the current reaction. What is sodium acetate used for?

Questions for self-control and protection of laboratory work:

1. What volume of potassium hydroxide is used to neutralize amino acid from 0.012 kg of acetic acid with a density of 1.140 g/ml at 15%? (Answer 65.5 ML).

2. What volume of ethyl alcohol is required for 1.5 kg of amino acid with a density of 96 percent (0.8 g/ml), if 2 times more alcohol is used to esterify amino acid?(Answer:2L.).

3. how much salt is formed when 15g of glycine reacts 10% (density 1.1 g/mL) with 91 ML? (Answer:19.4 g).