Obtaining and studying properties of the acids

Experience 1. Obtaining phosphoric acid

To test tube with distilled water put a few grains or drops of P₂O₅ to test the indicators(litmus methyl orange). Write the equation of Obtaining acid and their stepwise dissociation,call the acid residual of phosphoric acid.

Experience 2: interaction of acid with metals

To the test tube with 3-4 ml of diluted acid H₂SO₄ put a piece of zinc metal. The end of the experiment heat up the solution and observe whether the gas is released? As soon as the gas is stop releasing, stop heating, and allow to cool tube, upon cooling zinc sulfate crystals have to fall out. Write equations of the reaction.

Experience 3. Obtaining hydrochloric acid

To the tube wih vapor tube put some crystals of NaCl and pour 3-5ml concentrated H₂SO₄. Put down the end of vapor tube to 1-2ml of distilled water, then pour 1-2 drop of methyl orange. what happens? Write equation of the reaction. Call initial and obtained products

Experience 4. obtaining carbonic acid

To the tube wih vapor tube put a piece of marble CaCO₃ and pour 3-5ml concentrated HCl. Put down the end of vapor tube to 1-2ml of distilled water, then pour 1-2 drop of litmus. what happens? Write equation of the reaction. Call initial and obtained products.

Experience 4. obtaining silicic acid

To the tube wih sodium silicate Na2SiO3 pour HCl until precipitation of silicic acid. Write the equation in the molecular and ionic form.

LAB WORK 2. OBTAINING COMPLEX COMPOUNDS AND STUDY THEIR PROPERTIES

Experience 1. Obtaining nickel and copper ammine complex and their destruction

Pour to tube 3-2 ml solution of nickel sulfate and in another tube same amount of copper sulfate solution. Pour to each tube concentrated ammonia solution to precipitate hydroxides of copper and nickel. Then add ammonia solution to completely dissolve the precipitation, thereby forming a nickel and copper ammines [Ni(NН₃)₆]SO4, [Cu(NН₃)₆]SO₄. Indicate the color of solutions, experience the action of NaOH or Na₂S on the resulting solutions of complex salts of nickel and copper. Is it precipitated? Write the equation in molecular and ionic form. Make a conclusion of the complex durability of nickel and copper ions.

Experience 2. Obtaining mercury complex and study its durability

Pour to tube mercuric nitrate solution (II) and in small portions (dropwise from a pipette) add potassium iodide solution until precipitation of a bright orange precipitate of mercury iodide (II) HgI₂. Then add a few drops of a potassium iodide(KI) solution. Continue adding potassium iodide solution to dissolve the precipitate and form a clear light yellow solution of tetra-iodo merkurat (II) potassium. Write the equation in molecular and ionic form. Experience the action of NaOH or Na₂S on the resulting solutions of mercurycomplex salt.

Experience 3. Reactions of complex compounds

a) Add into the test tube 2-3 ml of a silver nitrate solution and the same amount of sodium chloride. The resulting precipitate dissolve in concentrated ammonia solution to form a silver complex salt. Put dawn into a solution a piece of granulated zinc. What you observe? Write the equation of reaction.

b)Add into the test tube 2-3 ml of a copper sulfate CuSO₄ solution and the same amount of K₃[Fe(CN)₆]. Indicate the color of formed precipitate of copper hexacyanoferrate. Write the equation in molecular and ionic form.

Experience 4. Obtaining cobalt complex

Pour into two tubes 2-3 ml of cobalt chloride solution(II) CoCl₂. In one tube add dropwise conc. hydrochloric acid solution until change color due to the formation of the complex ion [CoCl4]^2-.

In another tube add a few crystals of potassium thiocyanate KSCN, shake it to dissolve the crystals, and the solution changes color as form ion [Co(SCN4]^2-.

Hydrocarbons

Aim of work: laboratory methods to hydrocarbons and to hold them for chemical transformations

Experiment 1. The production of methane and their properties

Reagents and equipment:

sodium acetate anhydrous calcined

soda lime 1:2

Bromine water (saturated)

Potassium permanganate (diluted) 3:1

Sodium carbonate (5%) 2-3 ml

The vapor tube

Porcelain Cup

Method of operation

For experience carrying out pre-prepared two test-tubes: one test-tube of potassium permanganate, the other with bromine water.

In a dry test-tube is poured a mixture of dry sodium acetate and soda lime, closed tube vapor tube set propertiesfile with some tilt. Evenly heat the whole thing, and then most, where the air, then produce methane.

A gas outlet pipe successively introduced into a test-tube with potassium permanganate solution 0,5-1 minute, then the second test tube with bromine water. The solutions do not change their color, which suggests that alkanes in normal conditions react with potassium permanganate and bromine water.

Assignment: write reaction equations for methane production and combustion, and the conclusion about the attitude towards bromine water and oxidizing agent.