On patients in rural junior high school chemistry experiment on the use of resources

Abstract: In combination with the laboratory of carbon dioxide extraction, acid and metal oxide reaction experiments, for example about the use of life characteristics of teaching resources to do chemistry experiments chemistry experiments to save drugs, turning waste into treasure, to narrow the chemical and life distance, junior high school students to stimulate interest in chemistry.

Keywords: chemical experimental resources, stimulate, interest in learning chemistry

As a rural school for many years in junior high school chemistry teacher, chemistry experiments are often faced with the problem of insufficient investment in teaching equipment, after a period of exploration, I found that rural schools if they can make good use of their advantages, can make up for lack of teaching equipment caused by the loss. The author is currently on his own in the usual teaching, the specific use area of ​​chemistry teaching resources written a few articles to use for valuable feedback.

First, the living resources in the laboratory system, the use of carbon dioxide gas
1. Plastic bottles, old pen shell chemistry experiment
Now save the students point of view is rather weak, not much mind the concept of carbon, ball-point pen cartridge is exhausted, do not buy the cartridge, fling the ball-point pen shell, re-buy a new pen, I promptly seize this phenomenon educate students, and waste plastic bottle instead of using ordinary chemical reaction flask experiments, instead of the old ball-point pen shell glass tube.

2. The use of waste paper
Roll paper with a small stick for balance beam, beam center buckle a thin, buckle the other end of the stage in the metal framework to do the fulcrum of the balance. To find two identical disposable cups, paper cups, respectively, in the Department of the thin, thin line to beams at both ends and then do the balance of the "tray", the balance made of paper as shown below:
(1 The purpose of the instrument innovation
Under the same conditions, CO2 density than air, PEP P114 Figure 6-12 are not specifically verify the same experimental conditions, the density of carbon dioxide than air this nature, students tend to fire resistance and carbon dioxide density than air under same conditions large tell, the carbon dioxide chemical and physical properties of confused, I produced a paper balance, specializing in carbon dioxide density, so that students at a glance, under the same conditions, CO2 density than air.

(2 steps balance the paper
CO2 gas cylinders to collect two sets (set of cylinders the same specifications, regulate the balance of the balance, so that a student balance to the side of the paper cup paper dumping of CO2 gas bottle, filled with CO2 gas significantly decreased the side of the cup . and then another bottle of gas into the balance the other "tray", the balance beam and magically restore the balance slowly.

(3) experimental results
Through this experimental device operation, the students understand the density of CO2 under the same conditions than air, carbon dioxide can be dumped like a liquid, CO2 colorless, odorless, invisible intangible, more experimental facts allows students to truly "see" the "CO2" the existence of the junior high school students new to chemistry really feel wonderful material world.

3. Experiments in alternative medicine
(1) calcium carbonate
Preparation of the past to do laboratory experiments used carbon dioxide to calcium carbonate drugs are always looking for the school cafeteria instead of egg shells from the reform of 2006, I use my school is located in the coastal areas, close to the Yellow Sea is the world's two in the long One type of coast, and everywhere there are various resources of shells, I find a student to replace the calcium carbonate shells Preparation of carbon dioxide to do experiments, harvest is still very great, the students got a clam shell, clam shell son, snail shell, conch shell, as well as the students were even hired the squid cuttlebone.

(2 litmus
Students before class to find a variety of flowers arranged, pre-soaked with alcohol, with a gauze filter on the class, making the spot litmus reagents, the students see their obtained indicator come into play, great sense of accomplishment, excitement, exploration passion for the mysteries of chemical knowledge rose, resulting in learning chemical driving force.

(3 lime
I also ask students to prepare before class, students go back with some students who do not have, pestered Mom and Dad on Sunday after a difficult way to run all the way to find and some students with a large plastic bottle of Sprite brought to lime with operating drug book written paper label on the bottle onto the podium. I see students in irregular crooked on the label written on the drug name, chemical formula, very pleased, indicating that students master the chemical label, students see their own carbon dioxide limewater test from his face on the you can see them to have fun, and feel able to finally contribute to the class to do chemical experiments, and also train the students to explore the ability of co-operation.

Some parents are people, not attentive, did not follow my request to take the lime in the lime pond, is taken to the lime, and lime deposits in the following, I seize this rare time of teaching resources, it is good for students to make clear their links and differences, to obtain a better education and teaching effectiveness, class midterm exam score points in this knowledge was 89.43%. Links to free download http://www. hi138.com
Second, the rusty iron nails better than drugs
Sometimes the use of the waste of life than the factory to provide even better drugs. Many of prefectural-level cities in Jiangsu Province are on the junior high school, "Physical health experiment" to test, exam in chemistry experiments in several exercises and examiners found that the students do the chemical properties of the acid-base experiments "acid reaction with metal oxides "Fe2O3 with drugs provided by the manufacturer and HCl reaction, can not see the solution becomes yellow phenomenon, often due to experiment with Fe2O3 much left after the reaction, the solution remains red, mislead students FeCl3 solution is red and this The key to success is to experiment to get the little Fe2O3, only a small medicine spoon a little bit of the first pick.

Junior high school students to do chemistry experiments is not long, the chemical experiment is not high skills to take drugs, take drugs often can not control the amount, some students even think that the more experimental drugs more likely to achieve success, more oil is not bad food, Fe2O3 and HCl reaction The chemistry experiment is successful, it is difficult for junior high school students, we put this experiment into a common rust Fe2O3 nails, experimental results were quite good. rust before nails in the test tube, then add a colorless solution of HCl, HCl solution, an immediate response when confronted with rusty nails, colorless solution turned yellow, the experimental phenomenon is very obvious, experimental success rate was 100%, and easy to get drugs, why not do it! If the response is a long time, the surface of the nails rust will be removed and become light, to enhance the students understanding of the hydrochloric acid will rust Time little longer, and the surface of the nail still small bubbles, the students think of non-oxidizing acid reaction of hydrogen with metal active knowledge, while allowing students to practice basic operations, with the density of relatively large test tube to take nails, so that efficient use of economic resources in chemistry experiments.

In fact, the chemical comes from life, life in many chemical phenomena. There are many high school chemistry experiment in the use of chemical materials and medicines, such as Preparation of O2 in the experiment, I arranged the students to find a village health hydrogen peroxide, I purposely test O2 use in the classroom to do with Mars, broom sticks of wood to enable students to test O2. Life is full of resources for chemistry experiments, the key you are not conscientious, can not wash their brains, wash hands, there is no "digging three feet of the spirit" to collection and processing of life's chemical and effective experimental resources.

Need to learn chemistry into life, which is an important means of chemical experiments, the use of life or even waste materials for chemical experiments, it enables the chemical life, and the use of chemical knowledge to solve their problems, heart formation in students' chemistry is useful "point of view, determined to learn from the heart of chemical, with the confidence to worry that the initiation stage of chemical science is wrong about this!

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