LABORATORY TRAINING

Experiment 1. Interaction between oxides and water

To add a few grains of solid CaO, CuO, ZnO (total volume of each chemicals - near one match-head) into three tubes. To add 10-20 drops of distillated water into each tube. To mix a tube content. What oxides do directly react with water? To write a corresponding reaction.

Experiment 2. Preparation of insoluble hydroxides

To add separately 1-4 drops of each soluble Iron (III) salts (FeCl₃ or Fe₂(SO₄)₃), Copper (CuSO₄ or CuCl₂ or Cu(NO₃)₂), Manganese (II) (MnSO₄ or MnCl₂), and Nickel (NiSO₄), Cobalt (II) (CoSO₄ or CoCl₂) into tubes #1, 2, 3, 4, 5. To add 1-2 drops of any alkali into each tube. What do you observe? To write corresponding reactions. To point out color of precipitate in each tube. To explain why color of Manganese (II) Hydroxide is changed.

Experiment 3. Preparation of amphoteric hydroxides

To add 1 drop of any alkali (NaOH or KOH) into three tubes. To add by drops the solution of Aluminium salt (for example, Al₂(SO₄)₃) into tube # 1 up to the precipitate appearance; into tube # 2 - Zinc salt (for example, ZnSO₄) analogously to previous case; into tube # 3 - Chromium (III) salt (for example, Cr₂(SO₄)₃). To divide each prepared precipitate into two tubes. To add solution of any acid (for example, HNO₃) to the first part of precipitate, alkali solution up to the whole dissolving of precipitate - to the second one. What do you observe? To write corresponding reactions.

Experiment 4. Interaction of salts solution (metathesis)

To add 2-3 drops of BaCl₂ solution into tube # 1 and to drop the same quantity of Sodium Sulfate; 2-3 drops of Lead (II) Nitrate - into tube # 2 and to add 1-2 drops of Potassium Iodide; 2-3 drops of Cobalt (II) Sulfate into tube # 3 and to add 1-2 drops of Sodium HydroPhosphate. What do you observe? To write corresponding reactions.

To prepare a report of laboratory work in the next form:

LABORATORY WORK #1.

Chapter. Classification of inorganic substances

CHAPTER # 7. THEORY OF ELECTROLYTIC DISSOCIATION

Vocabulary

Sourses:

1. Introduction in General, Organic and Biochemistry, 7^th Edition, by Morris Hein, Leo R. Best, Scott Pattison and Susan Arena, Brooks/Cole Publishing Co., 2001. (Chapters 14-17.1, pp. 404-496);

2. http://www.dbhs.wvusd.k.12.ca.us/AcidBase/Arrehenius-AcidBase.html

3. http://www.dbhs.wvusd.k.12.ca.us/AcidBase/Strong-Weak-AcidBase.html

4. http://www.public.asu.edu/~jpbirk/CHM-115_BLKB/Chpt16/sld003-004.htm

5. http://www.unco.edu/chemquest/q22_r18.htm

1. Solutions

Suppose a lump of sugar is dropped into a glass of water. You know from experience that the sugar will dissolve. Sugar is described as “soluble in water”. By “soluble” we mean the capability of being dissolved. Examination of sugar-water mixture, even under a microscope, would not reveal any particles of sugar. Such a mixture is called “solution”. Solution is a homogenous mixture of two or more substances in a single phase. In solution, atoms, and molecules of charged particles - ions are thoroughly mixed, with the result that the mixture has the same composition and properties throughout.

In the simplest type of solution, such as sugar-water solution, the molecules of one substance are distributed around the molecules of another one. The dissolving medium in a solution is called solvent, and the substance dissolved in a solution is called solute. In general, the solute is the substance, which mass is less than 50% of total mass of solution.

Types of solutions. Solutions are formed in all three states - gaseous, liquid, and solid. Nine possible combinations of gases, liquids, and solids in solutions are summarized in Table 10.

Table 10. Types of solutions

Date: 2015-01-12; view: 803