IXClass
Topic: “GENERAL VIEWS”ABOUT ORGANIC SUBSTANCES"
(Lesson on learning new material)
Lesson format: teacher's story and demonstration of samples and models of organic substances.
In connection with the transition to concentric programs in grade IX, the basics of organic chemistry are studied and ideas about organic substances are laid. Below is the development of a two hour lesson which was conducted in class IX after studying the topic “Carbon and its compounds”.
Lesson objectives: form an idea of the composition and structure of organic compounds, their distinctive features; identify the reasons for the diversity of organic substances; continue to develop the ability to compose structural formulas using the example of organic substances; form an idea of isomerism and isomers.
Preliminary homework: remember how a covalent bond is formed in molecules of inorganic substances, how its formation can be graphically shown.
Materials and equipmentTo lesson: samples of organic substances (acetic acid, acetone, ascorbic acid, sugar - in factory packages with labels, paper, candle, alcohol lamp, dry fuel (urotropine), oil; samples of plastic and synthetic fiber products (rulers, pens, bows, buttons, flower pots, plastic bags, etc.); matches, porcelain cup, crucible tongs. Ball-and-stick models of methane, ethylene, acetylene, propane, butane, isobutane, cyclohexane. On each student table there is a bath with ball-and-rod models.
During the classes:
I. The teacher tells how the term “organic substances” originated.
Until the beginning of the 19th century, substances were divided by origin into mineral, animal and plant. In 1807, the Swedish chemist J. J. Berzelius introduced the term “organic substances” into science, combining substances of plant and animal origin into one group. He proposed to call the science of these substances organic chemistry. At the beginning of the 19th century, it was believed that organic substances cannot be obtained under artificial conditions; they are formed only in living organisms or under their influence. The fallacy of this idea was proven by syntheses of organic substances in laboratory conditions: in 1828, the German chemist F. Wöder synthesized urea, his compatriot A. V. Kolbe obtained acetic acid in 1845, in 1854 the French chemist P. E. Berthelot - fats, in 1861 by Russian chemist A.M. Butlerov - a sugary substance. (This information is pre-written on the board and closed; during the message, the teacher opens this recording.)
It turned out that there is no sharp boundary between organic and inorganic substances; they consist of the same chemical elements and can be converted into each other.
Question: On what basis are organic substances classified as a separate group, what are their distinctive features?
The teacher invites students to try to figure this out together.
II. The teacher shows samples of organic substances, names them and, if possible, indicates the molecular formula (for some substances the formulas are written in advance on the board and closed during the demonstrationwalkie-talkie, these entries open): acetic acid C 2 H 4 O 2 acetone C 3 H 6 O, ethyl alcohol (in an alcohol lamp) C 2 H 6 O, dry fuel methenamine C 6 H 12 N 4, vitamin C or ascorbic acid C 6 H 8 O 6, sugar C 12 H 22 O 11, paraffin candle and oil, which contain substances with the general formula C X H Y, paper consisting of cellulose (C 6 H 10 O 5) p.
Questions: What do you notice in common in the composition of these substances? What chemical property can you assume for these substances?
Students answer that all of the compounds listed include carbon and hydrogen. They are believed to be on fire. The teacher demonstrates the combustion of hexamine, a candle and an alcohol lamp, draws attention to the nature of the flame, successively introduces a porcelain cup into the flame of the alcohol lamp, hexamine and a candle, and shows that soot is formed from the candle flame. Next, the question of what substances are formed during the combustion of organic substances is discussed. Students come to the conclusion that carbon dioxide or carbon monoxide, pure carbon (soot, soot) can be formed. The teacher reports that not all organic substances are capable of burning, but they all decompose when heated without access to oxygen and become charred. The teacher demonstrates the charring of sugar when heated. The teacher asks to determine the type of chemical bond in organic substances based on their composition.
Next, students write down in their notebooks signs of organic matterentities: 1. Contain carbon. 2. Burn and (or) decompose to form carbon-containing products. 3. The bonds in molecules of organic substances are covalent.
III. The teacher asks students to formulate a definition according to
concept "organic chemistry". The definition is written down in a notebook. Orga
nic chemistry- the science of organic substances, their composition, structure,
properties and methods of production.
Syntheses of organic substances in laboratory conditions accelerated the development of organic chemistry; scientists began to experiment and obtain substances that are not found in nature, but correspond to all the characteristics of organic substances. These are plastics, synthetic rubbers and fibers, varnishes, paints, solvents, medicines. (The teacher demonstrates products made from plastics and fibers.) These substances are not organic in origin. Thus, the group of organic substances has expanded significantly, but the old name has been retained. In the modern understanding, organic substances are not those that are produced in living organisms or under their influence, but those that correspond to the characteristics of organic substances.
IV. The study of organic substances in the 19th century encountered a number of
difficulties. One of them is the “unclear” valency of carbon. Yes, on
For example, in methane CH 4 the valency of carbon is IV. In ethylene C 2 H 4, acetylene
C 2 H 2, propane C 3 H 8, the teacher suggests determining the valency yourself
students. Students find the valencies II, I and 8/3, respectively. Semi
the given valences are unlikely. So, to organic substances
methods of inorganic chemistry cannot be used. In fact, in the building
there are organic substances peculiarities: the valence of carbon is always IV,
carbon atoms are connected to each other into carbon chains. Teacher
proposes to construct structural formulas of these substances. Students in
construct structural formulas in notebooks and put them on the board:
For comparison, the teacher demonstrates ball-and-stick models of these substances.
After this, the teacher asks to graphically depict the formation of co-
valence bonds in methane, ethylene and acetylene molecules. Images
put on the board and discussed. ,
V. The teacher draws students' attention to the periodic table.
More than 110 chemical elements have now been discovered, all of them included in
composition of inorganic substances. About 600 thousand inorganic compounds are known. The composition of natural organic substances includes a few elements: carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus, and some metals. Recently, organic elemental substances have been synthesized, thereby expanding the range of elements that make up organic substances.
Question: How many organic compounds do you think are currently known? (Students name the expected number of knownorganic substances. Usually these numbers are underestimated compared to actualtical amount of organic substances.) In 1999, the 18 millionth organic substance was registered.
Question: What are the reasons for the diversity of organic substances? Students are asked to try to find them in what is already known about the structure of organic substances. Students name reasons such as: carbon compounds in chains of different lengths; connection of carbon atoms by simple, double and triple bonds with other atoms and with each other; many elements that make up organic substances. The teacher gives another reason - the different nature of carbon chains: linear, branched and cyclic, demonstrates models of butane, isobutane and cyclohexane.
Students write in their notebooks: The reasons for diversity are organicski connections.
1. Connection of carbon atoms in chains of different lengths.
Formation of single, double and triple bonds by carbon atoms
zey with other atoms and with each other.
Different character of carbon chains: linear, branched,
cyclical.
Many elements that make up organic substances.
There is another reason. (It is necessary to leave a place for its recording in the textfor the sake of.) Students must find it themselves. To do this, you can do laboratory work.
VI. Laboratory work.
Students are given balls and rods: 4 black balls with 4 holes each - these are carbon atoms; 8 white balls with one hole each - hydrogen atoms; 4 long rods for connecting carbon atoms to each other; 8 short rods - for connecting carbon atoms with hydrogen atoms.
Assignment: using all the “building material”, build a model of an organic substance molecule. Draw the structural formula of this substance in your notebook. Try to make as many different models as possible from the same “building material”.
Work takes place in pairs. The teacher checks the correct assembly of models and depiction of structural formulas, and helps students who have difficulties. 10-15 minutes are allotted for work (depending on the success of the class), after which the structural formulas are put on the board and the following questions are discussed: What do all these substances have the same? How are these substances different?
It turns out that the composition is the same, the structure is different. The teacher explains that such substances, the composition of which is the same, but the structure and therefore the properties are different, are called isomers. Under structure substances implies the order of connection of atoms, their relative arrangement in molecules. The phenomenon of the existence of isomers is called isomeriya.
VII. Definitions of the concepts “chemical structure”, “isomers” and “isomerism” are written down by students in a notebook after the structural formulas of isomers. And in reasons for the diversity of chemicals is entered fifthpoint - the phenomenon of isomerism of organic compounds.
The ability to construct structural formulas of isomers is practiced using the following examples: C 2 H 6 O (ethanol and dimethyl ether), C 4 H 10 (butane and isobutane). Using these examples, the teacher shows how to write an abbreviated structural formula:
The teacher suggests constructing isomers of the composition C 5 H 12) if it is known that there are three of them. After putting all the isomers on the board, the teacher draws students’ attention to the method of constructing isomers: decreasing the main chain each time and increasing the number of radicals.
Homework: learn notes in a notebook, construct isomers of the composition C 6 N M (there are 5 of them).
Lesson topic: “Introduction to organic chemistry”
Item
: Chemistry Class: 9
The purpose of the lesson
: Creating conditions for “immersion” in organic chemistry.
Lesson objectives:
Educational
. Study the chemical composition of organic substances, identify the difference between organic substances and inorganic ones, determine the subject of study of organic chemistry, the goals and objectives of organic chemistry.
Developmental.
Develop the ability to work with primary sources and additional information: highlight the main thing and draw up a supporting summary. Develop skills in conducting chemical experiments, observing safety rules. Develop the ability to observe, compare, and draw conclusions. Develop memory, logical thinking, attention.
Educational
. To cultivate neatness, hard work, patriotic, aesthetic and moral qualities.
Lesson type:
A lesson in learning new material.
Lesson technical support:
Multimedia projector, computer, equipment and reagents for conducting a chemical experiment.
Expected Result:
- define concepts: subject of organic chemistry, organic substances
- compare organic and inorganic substances
- know the goals and objectives of organic chemistry,
- name the names of organic scientists
- be able to identify organic substances in plant objects.
During the classes
Org moment.
Good morning, guys. Good morning, dear guests! Let's smile at each other! And let’s start our lesson in a good mood. I hope the lesson will be productive for you, and most importantly, useful!
I want to start the lesson with the words of M. Gorky: “First of all and most carefully, study chemistry. This is an amazing science, you know... Its keen, bold gaze penetrates into the fiery mass of the sun and into the darkness of the earth’s crust, into the invisible particles of your heart, and into the secrets of the structure of a stone, and into the silent life of a tree. She looks everywhere and, discovering harmony everywhere, persistently seeks the beginning of life..."
I .Challenge and goal setting stage
Today you will work in groups and pairs. And pay attention, we have 11th graders sitting in the third row. Why are they here? Yes, to help you study chemistry. Well, we will find out what section they are studying as the lesson progresses.
Open your notebooks and write down the number.
Guys, let’s make a cluster - write the words “chemicals” in the center of the notebook.We work in pairs. Each pair makes up its own cluster.
Cluster prepared on the board slide1
What associations do you have with these words? Label examples of chemicals that you are familiar with from everyday life around the words “chemicals.”
Slide 2
For two years, you and I studied one section of chemistry called “inorganic chemistry.” Look at the diagram and list the substances that are classified as inorganic substances.
Called inorganic substances (water, oxygen, etc....)
What substances have we not yet studied, name them?Sugar, starch, fats, proteins...
Here are two collections in front of you, look carefully, how are they similar and how are they different? What groups can you divide these collections into?
What branch of chemistry do you think studies these substances?organic chemistry.
Let's remember what we studied in the inorganic chemistry section.-9th grade.
What classes of substances exist in inorganic chemistry?Oxides, acids, salts, bases
What classes does the organic chemistry section study? -Grade 11
From today's lesson we begin to study the section - organic substances and the topic of our lesson (formulate):"Subject of organic chemistry."
Let's return to the cluster.
These organic substances are familiar to you. What is included in themcompound ? Do we know? - 9Class
What do they havestructure ? Do we know? -9th grade
Features How do they differ from inorganic substances?
Which substances are more numerous - organic or inorganic?(reasons for diversity ) - 9 Class
Look at page 214. Which substances are there more?
II . Content comprehension stage
Look how many questions we have! We will look for answers to the questions posed in class!
I suggest using the help of 11th grade.
Working with 11 Klaas
Group 1. How were organic substances obtained in ancient times? Why are these substances called organic?
Answer: All organic substances were obtained exclusively from waste products of plant and animal organisms or as a result of their processing. This is where the name “organic matter” comes from.
Group 2. What does organic chemistry study?
Answer: The branch of chemistry that studies organic substances came to be called organic chemistry.
Group 3. What chemical element is necessarily included in the composition of organic substances?
Answer:
All organic substances contain the chemical element carbon.
Question 4.
What other definition of organic chemistry can be given?
Answer.
Organic chemistry is the chemistry of carbon compounds(write the wording in your notebook).
Question 5.
Besides carbon, what chemical element is included in organic matter?
Answer.
In addition to carbon, all organic substances contain the chemical element hydrogen. May also include O, S, N and other elements(write the signs of chemical elements on the board).
Question 6.
What chemical property can be common to organic substances?
Answer.
All organic matter burns.
What substances are formed when organic substances burn?carbon dioxide and water (writing in a notebook in words and reaction ) conclusion about what was said
Guys, another interesting property of organic substances is the ability to char and decompose when heated. Let's take examples from life. What happens to foods containing starch and protein?Coal is formed.
If you overcook potatoes, pancakes, pancakes, bread, the starch contained in the potatoes and flour becomes charred. When eggs or meat burn, the protein contained in these foods is charred.
Guys, what happens if you put table salt and sugar on a hot frying pan?
Let's conduct an experiment (instructions) Why do you think table salt and sugar behave differently when heated?
These substances have different crystal lattices.
What is the crystal lattice of table salt and sugar?In table salt NaCl is an ionic crystal lattice, and in sugar C 12 N 22 ABOUT 11 - molecular.
What type of chemical bond is characteristic of organic substances.Covalent polar chemical bond ) conclusion about what was said
Guys, let's write it downsigns of organic substances:
1) contain carbon;
2) burn and (or) decompose to form carbon-containing products;
3) covalent chemical bond;
4) molecular crystal lattice
| Reagents | Description or outline of the experience | Equipment |
| Copper oxide (II) CuO, granulated sugar, lime water | Lime water A mixture of sugar and copper (II) oxide | 2 test tubes, a stopper with a gas outlet tube, a tripod, an alcohol lamp, matches, asbestos mesh, dry fuel. |
| Precautionary measures | Progress of the experiment | Notes |
| First, heat the entire test tube, and then its end. At the end of the experiment, remove the gas outlet tube from the limewater, then turn off the alcohol lamp. | Pour 0.2 g of granulated sugar and 2-3 times more copper oxide into a dry test tube (II), mix everything thoroughly and start heating. Record your observations. 1. What gas caused the limewater to become cloudy? Write the reaction equation. 2. What substance was formed on the cold walls inside the test tube? 3. What substance was formed from copper oxide (II)? Write the reaction equation between copper oxide (II) and carbon. Draw a conclusion about whether granulated sugar belongs to organic or inorganic compounds.) conclusion about what was said | Stop the experiment as soon as the lime water becomes cloudy. |
In the excited state, the valence of carbon is 4. And in all organic compounds, the carbon atom is always tetravalent.
The simplest formula in organic chemistry CH4 - methane. We use structural formulas.(Create a structural formula - grade 11) C lied3
Valency is indicated by dashes: one dash corresponds to the unit of valence of an atom of a chemical element.
What organic substances studied in the lesson can be added to the “cluster” we have compiled?oil, candle, propane, glucose, butane, dichloromethane, acetic acid, acetylene, ethane, etc.
What is the valence of carbon in organic compounds?In organic compounds, carbon is always tetravalent
What chemical property is common to organic compounds?Many organic substances burn or decompose when heated without the introduction of air.
What is the importance of organic matter in society?These are food, clothing, shoes, synthetic materials, polymers, energy carriers, medicines, synthetic detergents, various paints, varnishes, dyes, toothpaste, shampoos, etc.
What effect do organic substances have on the human body? (Roxana, Rita)
III . Reflection
Guys, today we learned that organic chemistry is studied. What chemicals are called organic. The concept of valency of chemical elements was revealed. We examined the importance of organic substances and showed, with the help of additional literature, the negative impact of some of them on the environment.
Have we answered the questions we asked at the beginning of the lesson?
Guys, you have tests on the topic you studied on your table. Let's test your knowledge (2-3min)
Choose one correct answer.C
lead 4
1. What does organic chemistry study?
A) All compounds formed in living organisms.
B) Compounds of carbon with hydrogen.
B) Carbon compounds, with the exception of oxides, carbides, salts.
2. Which compound is classified as organic?
A) Acetic acid.
B) Baking soda.
B) Table salt.
3. By 2005, the number of known organic compounds is......
A) About 1 million
B) About 15 million
B) About 2 million
4. What are the names of compounds consisting only of hydrogen and carbon?
A) Organic substances.
B) Minerals.
B) Hydrocarbons.
5. Mass fraction of carbon in methane CH4 equal to
A) 75%
B) 80%
B) 25%
C lead 5
IV . Summarizing
Guys, everyone has atable “Reflection on the student’s activities in the lesson.”
I ask you to fill out the table and give it to me.
V . Homework C lead 6
Study § 48+ notes, *task No. 1, 2 p. 216 (for everyone), *task No. 36 p. 216 for in-depth study.
Now imagine what will happen if organic matter disappears.
There will be no more wooden objects, no more ballpoint pens, no book bags, no more books and notebooks made from organic matter - cellulose. There will be no linoleum in the classroom; only metal legs will remain from the desks. Cars will not drive on the street - there is no gasoline, and only metal parts will remain from the cars themselves. Computer and TV cases will disappear. Pharmacies will be out of most medications, and there will be nothing to eat (all food also consists of organic compounds). There will be nothing to wash your hands with and nothing to put on yourself, because soap and cotton, wool, synthetic fibers, leather and leather substitutes, fabric dyes are all derivatives of hydrocarbons. And there will be no one to look at this world - all that will be left of us is salt water and a skeleton, because the organisms of all living beings consist of organic compounds.
Now you understand the role of organic compounds in nature and our lives
C lead 6 this is interesting
While you are reading this article, youreyes use organic compound- retinal , which converts light energy into nerve impulses. While you are sitting in a comfortable position,back muscles maintain correct posture thanks tochemical breakdown of glucose with the release of the required energy. As you understand,The gaps between nerve cells are also filled with organic substances - mediators (or neurotransmitters) that help all neurons become one. And this well-coordinated system works without the participation of your consciousness! Only organic chemists understand as deeply as biologists how intricately man is created, how logically the internal systems of organs and their life cycle are arranged. It follows that the study of organic chemistry is the basis for understanding our life! And high-quality research is the way to the future, because new drugs are created primarily in chemical laboratories.
Self-analysis of the lesson
teacher of chemistry and biology Utkina A.I.
The lesson was held in the 9th grade of the Proletarskaya Secondary School.
Subject lesson "» . The class size is standard, average in its abilities, six students are assigned to the 7th type of education. Therefore, I set the main developmental goal to enable children to be active participants in the educational process, by including them in solving educational problem situations to develop their logical thinking and maintaining attention through changing educational activities and reflecting on individual stages of the lesson.
Lesson "Introduction to Organic Chemistry"is the first lesson in the transition to the study of organic chemistry and is intended to give a general overview and place the main emphasis and concepts. This is especially important since we are starting a new section in chemistry, “Organic Compounds,” for which 10 hours are allotted.
Lesson type - a lesson in learning new material
Place of the lesson in the curriculum - lesson on introducing new material.
Level of lesson delivery: predicting ways to move students to the result specified by the learning goals based on feedback and overcoming possible difficulties in their work.
the main objective (for students) - in the process of practical activity, based on an analysis of the composition of substances, divide substances into organic and inorganic and confirm the prediction experimentally. The main task associated with the formation of activity experience is to enrich the student’s personal experience through an educational experiment and to establish by logical means the properties of organic substances.
The topic and content of the lesson predetermined the formulation of educational tasks:
- To cultivate neatness, hard work, patriotic, aesthetic and moral qualities.
- Continue the formation of tolerance through the implementation of certain types of collective work: updating knowledge, practical assignments, laboratory experience.
These tasks were solved in combination at all stages of the lesson. All stages are logically interconnected:
The organizational moment set the students up to achieve the goal: the goal of the lesson was communicated, the predicted result was announced, and motivation to realize the goal. All this made it possible to include students in the course of the lesson.
At the second stage of the lesson, updating knowledge and analyzing information, a differentiated approach was used: 11th grade students completed the task of the interaction of sugar with copper oxide and lime water. The task of systematizing and integrating knowledge (work - searching and deploying information) and finding a creative solution (task of drawing up reaction equations). Students of intermediate level of knowledge completed analytical tasks oncombustion of inorganic and organic substances. During my work, I carried out the necessary consultations in order to create a “success situation”.
I preferred to teach most of the educational material deductively. To do this, students were asked to answer questions, the answers to which previously acquired knowledge were voiced, and at the same time we began to study new material. This allowed me to use such important principles of didactics as scientific approach and accessibility.
Interdisciplinary connections have been implemented through the use of materials from biology and technology “This is interesting” during the presentation. Observing the principle of systematicity, we walked from the known to the unknown (the students knew the substances, but could not explain them), from simple to complex. It was impossible to do without a demonstration experiment, since it contributed to the development of skills in conducting a chemical experiment.
To check the level of knowledge acquisition, students completed a test control.
The following teaching methods were used during the work:
- Verbal (the role of organic substances for humans, etc.);
- Visual (demonstration of slides, test);
- Problem-search (individual and group tasks to predict the properties of substances)
- Heuristic
- Research (experiment);
- Laboratory method.
The combination of these methods in the lesson showed high efficiency. Optimal performance of students in the lesson was achieved by alternating types of learning activities at different stages of the lesson and in a calm, friendly environment. All this ensured that students were not overloaded.
Special attention was paid to homework instruction, as it requires an understanding of the topic as a whole.The final stage was the assessment of the lesson results, summing up and commenting on the students’ activities.
The purpose of the lesson is fulfilled, the tasks are realized.
Municipal Budgetary Educational Institution
Secondary School No. 14
named after Hero of the Soviet Union Bely S.E.
x. Beysuzhek the Second
LESSON DEVELOPMENT
ON THIS TOPIC: « ORGANIC
CHEMISTRY.
SUBJECT OF CHEMISTRY.
HISTORY OF ORGANIC DEVELOPMENT
CHEMISTRY".
Teacher: Grekova Margarita Anatolyevna
Direction: Natural science
2013
Explanatory note.
This work is presented in the natural sciences. The topic of the lesson is “Organic chemistry. Chemistry subject. History of the development of organic chemistry".
There are 8 students in the 10th grade: 3 boys, 5 girls. By social status: 4 students from intact families, 1 from single-parent families, 3 students from supported families. The psycho-emotional state of the class is normal, average level of development.
The course of the Organic Chemistry program in the 10th grade was developed on the basis of the author's chemistry program (Authors and compilers of the program: Novoshinsky I.I., Novoshinskaya N.S., M. "Russian Word" 2008), compiled on the basis of the Federal component of the state standard of general education in chemistry of the 10th grade in accordance with the existing concept of chemical education and implementing the principle of concentric course design. The authors of the textbook are Novoshinsky I.I., Novoshinskaya N.S. "Russian Word" 2009 Section: Introduction to organic chemistry. Organic chemistry in grade 10 is studied 2 hours a week. 68 hours per year.
Lesson objectives:
educational: Expand the subject of organic chemistry. Give an initial concept of organic substances, their structural features, properties in comparison with inorganic ones. AND
educational: Show the role of organic chemistry in the life of modern society. Formation of a scientific picture of the world. Formation of ideological concepts: about the material unity of substances, the cause-and-effect relationship between the structure and properties of organic substances.
developing: To develop students’ skills to compare, generalize, and draw analogies between inorganic and organic substances.
Lesson type: lesson explaining new material
Management methods:
are common: explanatory and illustrative
private: verbal-visual
specific: conversation
Interdisciplinary connections.
Biology. Topic: “Organic substances of cells”
Chemistry in medicine. Topic: “The importance of chemistry in medicine”
Equipment: Demonstration samples: collections of organic substances, materials and products made from them. Presentation, projector, multimedia equipment, laptop
Lesson script
Plan
1.Organizational moment
2.Introduction to the topic of the lesson
3.Explanation of new material
4. Consolidation
5.Homework
6. Lesson summary
During the classes
1.Organizational point: Greeting, checking attendance, communicating the topic of the lesson (slide 1) 2.Introduction to the topic of the lesson Starting from today's lesson, we begin to study a new section of chemistry - organic, which we will study until the end of the school year. Today in class we will have to look at the concept of organic chemistry and the characteristics of organic substances. Let's look at what two types all substances are divided into: organic and inorganic (slide 2)3.Explanation of new material:
Organic chemistry - a branch of chemistry that studies carbon compounds,
their structure, properties, methods of synthesis.
Organic are compounds of carbon with other elements.
Organic matter - These are compounds of carbon with hydrogen, oxygen, nitrogen and some other elements.
Today, organic chemistry is one of the largest and most important branches of chemistry. This is explained by the following circumstances: (slide 3)
The number of known organic compounds is increasing exponentially and today exceeds 18 million, while slightly more than 100 thousand are known inorganic substances.
Most modern industrial processes in the chemical industry involve reactions and the production of organic substances. These are medicines, means of increasing agricultural productivity, polymeric materials, dyes, food additives, cosmetics, plastics, construction
materials, household chemicals and much more - all these are products main
(multi-tonnage) or thin
organic synthesis.
Most of the processes occurring in living organisms and ensuring their existence are chemical reactions of organic substances. Organic chemistry is the chemistry of life.
Chemists have learned to synthesize very complex natural substances: carbohydrates, proteins, nucleic acids. In these cases, organic synthesis comes to the aid of biotechnology : Large molecules are constructed from simpler “building blocks” by “specially trained” microorganisms and cell cultures. Based on the achievements of organic chemistry, it develops Genetic Engineering , which is increasingly used for biological and medical purposes.
Features of the structure and properties of organic compounds(slide4)
Carbon is the only element of the Periodic Table whose atoms are capable of forming very long chains by connecting with each other. This explains the great variety of organic substances. Unlike inorganic molecules, organic molecules can have a huge relative molecular weight, reaching several millions.
The most important from a theoretical point of view are carbon and hydrogen compounds. (hydrocarbons) . All other classes of organic substances can be considered as derivatives of hydrocarbons, in which some of the hydrogen atoms are replaced by other atoms or groups of atoms.
3. Since organic substances, as a rule, contain hydrogen in addition to carbon, when burned they form carbon dioxide and water.
? Let's remember what types of chemical bonds exist and in what cases are they formed?
4. The most common type of bond between atoms in organic substances is covalent bond. Covalent polar bond formed between atoms C and O, C and H, C and N, covalent nonpolar bond formed between carbon atoms C and C. Also sometimes found in organic compounds ionic bond (in salts of carboxylic acids - between the acid residue and the metal) and intermolecular hydrogen bond (between molecules of alcohols, carboxylic acids, etc.).
Classification of agents(slide 5-7)
Natural – formed naturally, without human intervention. Natural organic substances and their transformations underlie the phenomena of Life. Therefore, organic chemistry is the chemical foundation of biological chemistry and molecular biology - sciences that study the processes occurring in the cells of organisms at the molecular level. Research in this area allows us to better understand the essence of living natural phenomena.
Artificial – conditions similar to natural substances, but innot found in wildlife. So, based on the natural organic compound cellulose, artificial fibers (acetate, viscose, etc.) are obtained.
Synthetic – created by man in laboratoryconditions, there are no similar substances in nature.These include, for example, synthetic rubbers, plastics, drugs, dyes, etc.
History of the development of organic chemistry(slide 8-10)
Prerequisites for occurrence.
At the end of the 18th - beginning of the 19th centuries. in the science of chemistry dominated by a doctrine called "vitalism"(from lat. - life). Proponents of vitalism argued that any substances of living nature can be formed in living organisms only under the influence of a special “vital force”. Thanks to this teaching, studies of the structure and properties of plant and animal substances became a separate branch of chemistry. Swedish chemist Jene Jacob Berzelius 1807 called it organic chemistry, and the subject of its study - organic substances (found in living organisms). With the development and improvement of chemical experiment, it became clear that organic substances can be synthesized from inorganic (or, as they were called before, mineral) outside any living organism, in a flask or test tube, but the name organic substances remained.
Development of organic chemistry(slide 11)
Main stages:
1824 – oxalic acid was synthesized (F. Wöller);
1828 – urea (F.Wöller);
1842 – aniline (N.N. Zinin);
1845 – acetic acid (A. Kolbe);
1847 – carboxylic acids (A. Kolbe);
1854 – fats (M. Berthelot);
1861 – sugary substances (A. Butlerov )
In 1928, Wöller showed that an inorganic substance, ammonium cyanate, when heated, turns into a waste product of an animal organism, urea.
In 1845, Kolbe synthesized the organic substance acetic acid; he used charcoal, sulfur, chlorine and water as starting materials. In a relatively short period, other organic acids were synthesized, which were previously isolated only from plants.
In 1854, Berthelot managed to synthesize substances belonging to the class of alcohols.
In 1861, A.M. Butlerov, using lime water on paraformaldehyde, was the first to synthesize methylenenitane, which is a sugar that plays an important role in the life processes of organisms.
Comparison of properties of organic and inorganic substances
(table). Independent work of students with the table.
4. Fastening
Questions to consolidate knowledge:
1. How were organic substances obtained in ancient times? Why are these substances called organic?
ANSWER: All organic substances were obtained exclusively from waste products of plant and animal organisms or as a result of their processing. This is where the name “organic matter” comes from.
2. What does organic chemistry study?
ANSWER: The branch of chemistry that studies organic substances began to be called organic chemistry.
3. Who introduced the concepts of “organic substances” and “organic chemistry”?
Answer. J. Ya. Berzelius.
4. What chemical element is necessarily included in the composition of organic substances?
ANSWER: All organic substances contain the chemical element carbon.
5. What other definition of organic chemistry can be given?
ANSWER: Organic chemistry is the chemistry of carbon compounds.
6. Besides carbon, what chemical element is included in organic matter?
ANSWER: In addition to carbon, all organic substances contain the chemical element hydrogen. O, S, N and other elements may also be included.
Now imagine what will happen if organic matter disappears.
There will be no more wooden objects, no more ballpoint pens, no book bags, no more books and notebooks made from organic matter - cellulose. There will be no linoleum in the classroom; only metal legs will remain from the desks. Cars will not drive on the street - there is no gasoline, and only metal parts will remain from the cars themselves. Computer and TV cases will disappear. Pharmacies will be out of most medications, and there will be nothing to eat (all food also consists of organic compounds). There will be nothing to wash your hands with and nothing to put on yourself, because soap and cotton, wool, synthetic fibers, leather and leather substitutes, fabric dyes are all derivatives of hydrocarbons. And there will be no one to look at this world - all that will be left of us is salt water and a skeleton, because the organisms of all living beings consist of organic compounds.
Now you understand the role of organic compounds in nature and our lives
5. Homework:
Introduction, paragraph 1, summary, table
Abstracts on the topic “A.M.Butlerov”, “The importance of organic chemistry”
6. Results: Thus, today we got acquainted with organic substances, how they differ from inorganic ones, and studied the history of the development of organic chemistry. And we became convinced that organic substances play a huge role in our lives. Lesson grades.
The topic “Subject of organic chemistry” is offered for study. The role of organic substances in human life." The teacher covers the question of why there was a need to divide substances into organic and inorganic. Next, he tells students about the carbon cycle in nature, defines organic substances, and explains what hydrocarbon derivatives and organogens are. At the end of the lesson, the teacher will reveal the role of organic chemistry in our lives.
Topic: Introduction to organic chemistry
Lesson: Subject of organic chemistry.The role of organic substances in human life
By the beginning of the 21st century, chemists had isolated millions of substances in their pure form. At the same time, more than 18 million compounds of carbon and less than a million compounds of all other elements are known.
Carbon compounds are mainly classified as organic compounds.
Substances began to be divided into organic and inorganic from the beginning of the 19th century. Organic substances were then called substances isolated from animals and plants, and inorganic were substances extracted from minerals. It is through the organic world that the main part of the carbon cycle in nature passes.
From compounds containing carbon to inorganic traditionally include graphite, diamond, carbon oxides (CO and CO 2), carbonic acid (H 2 CO 3), carbonates (for example, sodium carbonate - soda Na 2 CO 3), carbides (calcium carbide CaC 2), cyanides (potassium cyanide KCN), rhodanide (sodium rhodanide NaSCN).
A more precise modern definition: organic compounds are hydrocarbons and their derivatives.
The simplest hydrocarbon is methane. Carbon atoms can combine with each other to form chains of any length. If in such chains carbon is also bonded to hydrogen, the compounds are called hydrocarbons. Tens of thousands of hydrocarbons are known.
Models of molecules of methane CH 4, ethane C 2 H 6, pentane C 5 H 12
Hydrocarbon derivatives are hydrocarbons in which one or more hydrogen atoms are replaced by an atom or group of atoms of other elements. For example, one of the hydrogen atoms in methane can be replaced by chlorine, or an OH group, or an NH 2 group.
Methane CH 4, chloromethane CH 3 Cl, methyl alcohol CH 3 OH, methylamine CH 3 NH 2
Organic compounds, in addition to carbon and hydrogen atoms, may include atoms of oxygen, nitrogen, sulfur, phosphorus, and less commonly halogens.
To appreciate the importance of the organic compounds that surround us, let’s imagine that they suddenly disappeared. No wooden objects, books or notebooks, no book bags or ballpoint pens. The plastic casings of computers, televisions and other household appliances have disappeared; telephones and calculators are gone. Transport is at a standstill without gasoline and diesel fuel, most medicines are missing and there is simply nothing to eat. There are no detergents, clothes, and neither of us...
There are so many organic substances because of the way carbon atoms form chemical bonds. These small atoms are capable of forming strong covalent bonds with each other and with nonmetal organogens.
In the ethane molecule C 2 H 6 there are 2 carbon atoms bonded to each other, in the pentane molecule C 5 H 12 there are 5 atoms, and in the well-known polyethylene molecule there are hundreds of thousands of carbon atoms.
Studies the structure, properties and reactions of organic substances organic chemistry.
Chemistry. Grade 10. Profile level: academic. for general education Institutions / V.V. Eremin, N.E. Kuzmenko, V.V. Lunin. – M.: Bustard, 2008. – 463 p.
ISBN 978-5-358-01584-5
Chemistry. Grade 11. Profile level: academic. for general education Institutions / V.V. Eremin, N.E. Kuzmenko, V.V. Lunin. – M.: Bustard, 2010. – 462 p.
Khomchenko G.P., Khomchenko I.G. Collection of problems in chemistry for those entering universities. – 4th ed. – M.: RIA “New Wave”: Publisher Umerenkov, 2012. – 278 p.
Tutorial on the Internet
Samara State University.
Department of Organic, Bioorganic and Medical Chemistry
Chemistry 9th gradeLesson Introduction to organic chemistry.
Theory of the structure of organic substances A.M. Butlerov.
Target:
To acquaint students with the basic prerequisites for the creation, provisions and significance of the theory of the structure of organic compounds by A. M. Butlerov.
Lesson objectives:
Educational - to study the history of the emergence of organic chemistry and the prerequisites for the creation of the theory of chemical structure, its main provisions, the dependence of the properties of substances on the structure of the molecule, the importance of the theory of structure for the development of science and human life. Deepen basic chemical concepts: substance, chemical reaction.
Developmental - develop students’ ability to compare, analyze and apply information from other areas of knowledge
Educational – to promote the formation of a natural science picture of the world in students.
Equipment:
Interactive whiteboard, flipchart “Butlerov’s Theory”, presentations “Choose an organic substance”, “Choose the formula of an organic substance”, “Test your knowledge on the classification of substances”, video “A.M. Butlerov”, survey sheet with test tasks.
Lesson type: learning new material.
Teaching methods: partially search-based, visual.
Forms of organization of cognitive activity: group, frontal, practical.
During the classes
1.Org. moment.
2. Frontal survey
What is the subject of study in chemistry? (substance)
What are the substances? (simple and complex)
In grades 8-9 we studied complex substances belonging to only 4 classes. And from this lesson we will study 12 classes of substances. Moreover, each of these classes has its own characteristic properties that you need to know very well.
We will repeat with you the classification of inorganic substances.
An example is written on one side of the card, and the answer is written on the other. Think and solve the problem. After that, you can test yourself by left-clicking on the card. Work with the presentation at the blackboard “Test your knowledge on the classification of substances.”
3. Stage of updating knowledge.
But since inorganic ones exist, does that mean there are organic ones too? Where did we meet them? (in biology.) Work with the presentation at the board “Choose an organic substance.” So what are organic matter?
4.Stage of learning new material
The topic of the lesson is “Introduction to organic chemistry. Theory of the structure of organic substances A.M. Butlerov".
The time of humanity's acquaintance with them is measured in millennia. When, wrapped in animal skins, our ancestors crowded around the fire that warmed them, they used only organic substances. Food, clothing, fuel.
In the distant period of humanity’s childhood in sunny Greece and powerful Rome, people knew how to prepare ointments. The art of dyeing fabrics flourished in Egypt and India. Vegetable oils, animal fats, sugar, starch, vinegar, resins, dyes were isolated and used in that era.
In 1808, the Swedish scientist J.Ya. Berzelius proposed to call organic substances those obtained from plant and animal organisms. Humanity has been familiar with such substances since ancient times. People knew how to extract vinegar from sour wine, essential oils from plants, extract sugar from sugar cane, and extract natural dyes from plants and animals. And the branch of science about such substances is organic. Chemists divided all substances depending on the source of their production into mineral (inorganic), animal and plant (organic).
Writing the formula of an organic substance according to Berzelius:
For a long time it was believed that to obtain organic substances, a special “vital force” is needed - vis vitalis, which acts only in living organisms, and chemists are only able to isolate organic substances from waste products, but cannot synthesize them. Therefore, the Swedish chemist J.Ya. Berzelius defined organic chemistry as the chemistry of plant or animal substances formed under the influence of “vital force.”
Advances in the synthesis of organic compounds, as a result of which the doctrine of vitalism, that is, the “vital force”, under the influence of which organic substances are supposedly formed in the body of living beings, was dispelled:
in 1828, F. Wöhler synthesized urea from an inorganic substance (ammonium cyanate);
in 1842, the Russian chemist N.N. Zinin obtained aniline;
in 1845, the German chemist A. Kolbe synthesized acetic acid;
in 1854, the French chemist M. Berthelot synthesized fats, and finally
in 1861 A.M. Butlerov himself synthesized a sugar-like substance.
As a result, we came to the following concept of organic matter:
Currently, about 18 million organic substances and less than 1 million inorganic substances are known. When studying organic chemistry, we will come across substances with interesting properties: the most persistent odor that does not disappear even after 800 years (3-methylcyclopentadecanone-1 or muscone, part of natural musk); the sweetest taste, 33,000 times sweeter than sugar (methylphenyl ester of L-a-aspartylaminomalonic acid, created by Japanese scientists); a substance whose presence in a person’s blood improves his mood and reduces stress (phenylethylamine, found in chocolate).
DNA isolated from human mitochondria is included in the Guinness Book of Records because its name, compiled according to all the rules of chemical nomenclature, contains about 207 thousand letters!
Question: What question immediately arises in a thinking person’s mind? Why did carbon compounds become the subject of study for an entire section of chemistry?
But in organic chemistry of the 19th century, “contradictions” accumulated: (fishbone technique)
The variety of substances is formed by a small number of elements.
C, N, H, O, S.
Apparent valency discrepancy in organic substances.
(determine the valency of carbon in the proposed formulas)
IV I III I 2.666…I
C H4 C2 H6 C3 H8
Methane Ethane Propane
Various physical and chemical compounds that have the same molecular formula.
C2H6O – alcohol and ether.
С6Н12О6 - glucose and fructose
C4H10O – butyl alcohol and ether.
We need a theory that unites all these inconsistencies.
The decisive role in creating the theory of the structure of organic compounds belongs to the great Russian scientist Alexander Mikhailovich Butlerov. On September 19, 1861, at the 36th Congress of German Naturalists, A.M. Butlerov published it in his report “On the Chemical Structure of Matter.”
Basic provisions of the theory of chemical structure of A.M. Butlerov
(→ write down)
→All atoms that form molecules of organic substances are connected in a certain sequence according to their valency
(Task 1-2. Make a model of a substance from the proposed “atoms” of the composition CH4 and C2 H6. Write structural formulas. Teacher’s explanation. For task 3- Make a model of a substance from the proposed “atoms” of the composition C3H8, students do it on the board)
→The properties of a substance depend not only on which atoms and how many of them are included in the molecules, but also on the order of connection of atoms in the molecules.
(Task 4. Make a model of a substance with the composition C4H10. Write the structural formulas. Ask students to compose the formula for n-butane, and the teacher does it for isobutane) These substances differ in physical properties: butane has a boiling point of 0C, and isobutane - -11.0C.
→Isomers are substances that have the same molecular composition, but different chemical structures of the molecules.
→By the properties of a given substance one can determine the structure of its molecule, and by the structure of the molecule one can predict the properties.
Let's look at an example. There are two substances with the molecular formula C2H6O. One of them reacts with sodium, while the other does not react. What are their formulas? Two formulas were created. In the first option, the hydrogen of the hydroxyl group must be mobile, and it will be replaced by sodium. In the second case, the molecule is symmetrical and therefore does not react with sodium. (When explaining, the left side of the reactions is demonstrated first, and then the right)
→Atoms and groups of atoms in molecules of substances mutually influence each other.
Let's look at an example. Sodium hydroxide, aluminum hydroxide and sulfuric acid have an OH group in their structure. (Determine the oxidation states in them). But in reactions, bonds are broken in different ways. In sodium hydroxide between sodium and oxygen, in aluminum hydroxide and between metal and oxygen, and between oxygen and hydrogen, and in sulfuric acid only between oxygen and hydrogen, since the central atom has different electronegativity and oxidation state in different cases - this and becomes the cause of the manifestation of different types of compounds: sodium hydroxide is basic, aluminum hydroxide is amphoteric, sulfuric acid is acidic. (At the beginning of the explanation, the upper part of the record is shown, at the end the lower part opens)
5. Fixing the material
1. Let's return to the fishbone pattern. Prove that there are no such inconsistencies.
2. Work with the task: “Choose the formula of an organic substance”
3. The riddle is the opposite
BUTLEROV will be the first to understand the molecule code,
Prove: neighbors can change the properties of an atom.
As proof, he gives a convincing example -
He took BUTANE, changed the order, gets REMOZI. (ISOBUTANE)
5. Assignment. Write the structural formulas of C5H12. (independent work in a notebook, with checking on the board)
6.Conclusions
Theory of the chemical structure of substances by A.M. Butlerov
- made it possible to systematize organic substances;
- answered all the questions that had arisen by that time in organic chemistry;
- made it possible to theoretically foresee the existence of unknown substances and find ways of their synthesis.
Its further development of the theory of A.M. Butlerov received in stereochemistry - the study of the spatial structure of molecules and the study of the electronic structure of atoms.
7. Reflection.
How do you rate the lesson? (Mark it on a piece of paper.)
8. Summing up the lesson.
