chemistry lesson

Practical work # 1 on the topic "Solving experimental problems for the determination of plastics and fibers" - the STRUCTURE of MATTER-LESSON DEVELOPMENTS in CHEMISTRY 11 class - lesson developments-lesson developments-author's lessons - plan-lesson summary - chemistry

Objectives of the lesson: to improve practical skills in performing a chemical experiment, observing the rules of OT and TB: to teach you to experimentally determine the specified plastics and fabrics, observing the rules of OT and TB; to work with an alcohol lamp, heat substances in an open flame, using a spoon to burn substances, a test tube; to correctly identify substances by smell.

Equipment: sets of plastics and fibers according to options, plastics based on: polyethylene, polyvinyl chloride, polystyrene, fabrics based on cotton fiber; wool, nylon, acetate.

Lesson progress

I. Organizational moment

Students should set the main goals and objectives of the lesson.

Spend:

a) training on health and safety:

b) instructing how to perform the work (consistency, accuracy);

C) instruct the design of the work on each plastic and each fabric, experimentally determine on the basis of which polymer the product is made, and then give a description of the polymer according to the plan:

1. The appearance of the product.

2. Attitude to heating:

— color change;

— softens;

— melts;

— there is a smell;

— it is possible or not to pull the thread.

3. Burning:

— flame color;

— lights steadily or intermittently;

— does it smoke or not;

— is it burning outside the flame or not;

— I can smell it."

4. Decomposition:

— as the products of decomposition act on the indicator;

— how the decomposition product interacts with VG₂; I₂.

5. for fabrics, the design principle is the same, it should only be noted whether the ash left after combustion is ground.

6. the conclusion is Made: plastic, fabric, on the basis of which polymer.

Characteristics of the polymer:

1) Structural formula; a monomer.

2) synthesis Reaction (make an equation);.

3) Positive and negative qualities of the polymer.

4) application Areas.

III. Performing practical work on options

In the course of the experiment, the teacher observes the correctness of compliance with OT and TB by students at the time of determining plastics and fibers.

III. Generalizations and conclusions from the lesson

The significance of performing this work for you is as follows:

- acquired practical skills in the determination of polymers based on which plastics and fabrics are made;

— learned to observe the basic rules of OTT and TB when burning plastics, fabrics;

— we concluded that it is environmentally dangerous to burn plastics and fabrics, since IUD decomposes into their component compounds when heated, which burn longer or remain in the same form in the air, can be dissolved in water, soil. All this affects the existence of living organisms in nature. It can lead to environmental disasters.

IV. Homework assignment

Repeat section 6-9 on the subject "structure of matter". Prepare for test # 2.