Topic: Carbon and its compounds with hydrogen part 1

Target group

Elementary school student (grades 7. and 8.)

Core curriculum:

Elementary school. Chemistry.

VIII. Compounds of carbon with hydrogen - hydrocarbons. Pupil:

1) defines the terms: saturated hydrocarbons (alkanes) and unsaturated hydrocarbons (alkenes, alkynes);

2) creates a general formula of the homologous series of alkanes (based on the formulas of successive alkanes) and writes the total formula of the alkane with the specified number of carbon atoms; draws structural and semi‑structural (group) formulas of alkanes with straight‑to‑five carbon atoms in the molecule; gives their systematic names;

3) observes and describes the physical properties of alkanes; indicates the relationship between the length of the carbon chain and the physical properties in a series of alkanes (density, melting point and boiling point);

4) observes and describes the chemical properties (combustion reactions) of alkanes; writes the equations for combustion of alkanes with high and low oxygen availability; finds and exchanges information on the applications of alkanes;

5) forms general formulas of homologous series of alkenes and alkynes (based on the formulas of subsequent alkenes and alkynes); writes the total formula of the alkene and alkyne with the specified number of carbon atoms; it forms the names of alkenes and alkynes based on the names of the corresponding alkanes; draws structural and semi‑structural (group) formulas of alkenes and alkynes with straight‑chain atoms up to five carbon atoms;

6) on the basis of the observations describes the physical and chemical properties (combustion, bromine incorporation) of ethene and ethn; searches for and uses information about their uses;

8) designs and conducts experiments to distinguish saturated hydrocarbons from unsaturated hydrocarbons.

General aim of education

The student preserves information about coal and its hydrogen compounds.

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• to characterize alkanes, alkenes and alkynes;

• to discuss what organic compounds are;

• to describe the chemical properties of hydrocarbons;

• to distinguish saturated hydrocarbons from unsaturated hydrocarbons;

• to determine the decisive factor for hydrocarbon combustion reaction products;

• to explain why you can not use a malfunctioning gas stove and exchange possible hazards.

Methods/techniques

• expository

  • talk.

• activating

  • discussion.

• programmed

  • with computer;

  • with e‑textbook.

• practical

  • exercices concerned.

Forms of work

• individual activity;

• activity in pairs;

• activity in groups;

• collective activity.

Teaching aids

• e‑textbook;

• interactive whiteboard, tablets/computers;

• sheets of gray paper;

• colored markers.

Lesson plan overview

Introduction

1. The teacher hands out Methodology Guide or green, yellow and red sheets of paper to the students to be used during the work based on a traffic light technique. He presents the aims of the lesson in the student's language on a multimedia presentation and discusses the criteria of success (aims of the lesson and success criteria can be send to students via e‑mail or posted on Facebook, so that students will be able to manage their portfolio).

2. The teacher together with the students determines the topic – based on the previously presented lesson aims – and then writes it on the interactive whiteboard/blackboard. Students write the topic in the notebook.

Realization

1. The teacher discusses the issue of organic chemistry with students. He divides chemistry into inorganic and organic, analyzing the scheme in the abstract. He mentions the achievements of Friedrich Wöhler.

2. Students will get acquainted with the content of the abstract. Then, working in pairs, they analyze the illustrations in it.

3. The teacher divides the class into small groups. Each receives a sheet of gray paper and colored pens. Students prepare a map of concepts devoted to the issue of carbon and its compounds with hydrogen After completing the activities, the group leaders present the maps created in teams.

4. The students check their knowledge about carbon and its compounds with hydrogen, working with the tabs placed in the abstract.

5. The students carry out interactive exercises number 1–3. The teacher and the students discuss the correct solutions .

Summary

1. Selected students explain in own words the meaning of a word or concept indicated by the teacher.

2. The teacher asks the students to finish the following sentences:

   • Today I learned ...

   • I understood that …

   • It surprised me …

   • I found out ...

   The teacher can use the interactive whiteboard in the abstract or instruct students to work with it

Homework

1. Carry out exercise number 4.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Carbon and its compounds with hydrogen part 1

1828 is considered a breakthrough year in the development of organic chemistry. At that time, the German chemist Friedrich Wöhler obtained an organic substance (urea) from an inorganic salt in the laboratory conditions. In this way, belief that these compounds can only be produced by living organisms due to their vital force was debunked. The classification of chemical knowledge into inorganic and organic is historical, but it is still in use today.

Organic compounds are chemical compounds of carbon with other elements despite the compounds classified as inorganic (i.e. carbon oxides, carbonic acid and its salts).

Hydrocarbon are compounds of carbon and hydrogen. Mixture of hydrocarbons are for example oil, paraffin, gasoline or gas in air tanks.

We can divide hydrocarbons into:

• saturated, alkanes – in which molecules all bonds between carbon atoms are single,

• unsaturated, alkenes – in which molecules have one double bond between carbon atoms, the remaining bonds are single; alkynes – in which molecules have one triple bond between carbon atoms, the remaining bonds are single.

Depending on the conditions the products of combustion of hydrocarbons are:

• for complete combustion: carbon dioxide and water,

• for incomplete combustion: carbon monoxide and water, carbon (soot) and water.

• Natural sources of hydrocarbons are natural gas, crude oil and fossil carbons.

• Saturated hydrocarbons (alkanes) are hydrocarbons in which the molecules between carbon atoms have only single bonds.

• To unsaturated hydrocarbons we include hydrocarbons, in which molecules between carbon atoms in addition to single bonds there is one double bond (alkenes), and hydrocarbons, in which molecules between carbon atoms there is one triple bond (alkynes).