Carbon and Its Compounds, Atomic Properties, Allotropes, Types and Uses of Coal for SS 1

Class: SS 1
Term: Third Term
Week: 8
Age: 15 years
Duration: 60 minutes
Subject: Chemistry
Curriculum Theme: The chemistry and the Environment
Focal competence: Identifying the structure, practical applications and importance of carbon
Key competencies/values: Creativity and Innovation; Environmental Literacy; Innovation
Skills:

• identify the position of carbon on the Periodic Table
• describe the structure of carbon

Previous Lesson: Pure and Impure Water, Water Contaminants and Purification
Topic: Carbon And Its Compounds
Subject Matter: Meaning of Carbon and its Compounds, Atomic number, mass number, valency and relative atomic mass of carbon, Allotropes of carbon, Types and uses of coal

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• identify the position of carbon on the Periodic Table;
• describe the structure of carbon;
• state the atomic number, mass number, valency and relative atomic mass of carbon;
• identify various substances in and around us that contain carbon;
• describe the unique characteristics of carbon as an element;
• define the term allotrope;
• identify the isotopes of carbon;
• explain the relationship between the structure of carbon and the existence of many natural and synthetic carbon containing compounds;
• explain the uses of carbon to life and the society;
• explain the importance of carbon to life and the society;
• write the chemical symbol and formula of carbon;
• list the allotropes of carbon.

Affective Domain

• appreciate the widespread importance of carbon and its compounds;
• develop an interest in the study of organic chemistry.

Psychomotor Domain

• draw the electron structure of carbon;
• handle samples of carbon-containing materials carefully.

Social Domain

• collaborate effectively in group activities to identify carbon compounds.

Reference Materials

The following resources were used in planning this lesson:

• 2025 New Revised Senior Secondary Education Curriculum (SSEC)
• Relevant State Unified Scheme of Work
• Essential Chemistry for Senior Secondary Schools
• The HeadTeacher Scheme of work For The New Revised Senior Secondary Education Curriculum (SSEC)

Instructional Materials

The teacher will teach this lesson with the aid of:

• Periodic Table chart
• Samples of carbon (e.g., charcoal, graphite pencil lead, diamond imitation)
• Samples of limestone, shells, fruits (as examples of carbon compounds)
• Glass vessels
• Whiteboard and markers

Rationale for the Lesson

This lesson introduces students to carbon, a fundamental element crucial for all known life and a vast array of materials. Understanding carbon’s unique properties, such as its ability to form diverse compounds, is essential for comprehending organic chemistry and its applications in daily life, from fuels to plastics and biological molecules. It also highlights the environmental impact and importance of carbon compounds.

Prerequisite/Previous Knowledge

Students should have basic knowledge of elements, atoms, atomic structure, and the Periodic Table from previous chemistry lessons.

Lesson Content/Board Summary

Carbon And Its Compounds

Meaning of Carbon and its Compounds

Carbon is a non-metallic element with the chemical symbol C. It is a fundamental building block of all known life and forms an enormous number of compounds. Carbon compounds are chemical substances that contain carbon atoms, often bonded with other elements like hydrogen, oxygen, nitrogen, and sulfur. These compounds are central to organic chemistry.

Atomic Properties of Carbon

Carbon is located in Group 14 and Period 2 of the Periodic Table.

1. Atomic Number: 6 (This indicates 6 protons and 6 electrons in a neutral carbon atom).
2. Mass Number: 12 (The most common isotope, Carbon-12, has 6 protons and 6 neutrons).
3. Valency: 4 (Carbon is tetravalent, meaning it can form four covalent bonds. This ability is due to its electron configuration of 2, 4, allowing it to achieve a stable octet by sharing four electrons).
4. Relative Atomic Mass: Approximately 12.01 g/mol (based on the average mass of its isotopes).

Unique Characteristics of Carbon:

1. Catenation: Carbon atoms have the unique ability to bond with other carbon atoms to form long chains, branched chains, and rings. This property leads to the formation of a vast number of organic compounds.
2. Multiple Bonding: Carbon can form single, double, and triple covalent bonds with other carbon atoms and with atoms of other elements (e.g., C=C, C≡C, C=O).
3. Small Atomic Size: Its small size allows for strong and stable bonds.

Allotropes of Carbon

Allotropy is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes. Allotropes show different physical properties but similar chemical properties.

Carbon exhibits allotropy, existing in various forms:

1. Crystalline Allotropes: These have a definite, regular arrangement of atoms.
   1. Diamond: Each carbon atom is sp3 hybridized and covalently bonded to four other carbon atoms in a tetrahedral arrangement. It is the hardest known natural substance, a poor conductor of electricity, and has a high melting point.
   2. Graphite: Each carbon atom is sp2 hybridized and bonded to three other carbon atoms in a hexagonal planar layer. These layers are held together by weak Van der Waals forces. It is soft, slippery, a good conductor of electricity, and used as a lubricant and in pencil leads.
2. Amorphous Allotropes: These forms lack a regular, ordered structure. They are often impure forms of carbon.
   1. Coal: A fossil fuel formed from decomposed plant matter.
   2. Coke: Obtained by heating coal in the absence of air (destructive distillation). Used as a reducing agent in metallurgy.
   3. Charcoal: Obtained by heating wood in the absence of air. Used as a fuel and adsorbent.
   4. Lampblack (Soot): Produced by incomplete combustion of hydrocarbons. Used in printing inks and rubber.

Isotopes of Carbon: Carbon has several isotopes, which are atoms of the same element with the same atomic number but different mass numbers (due to different numbers of neutrons).

1. Carbon-12 ((^{12}text{C})): The most abundant and stable isotope (6 protons, 6 neutrons).
2. Carbon-13 ((^{13}text{C})): A stable isotope (6 protons, 7 neutrons).
3. Carbon-14 ((^{14}text{C})): A radioactive isotope (6 protons, 8 neutrons) used in radiocarbon dating.

Types and Uses of Coal

Coal is a combustible black or brownish-black sedimentary rock, formed from ancient vegetation. It is classified based on its carbon content and geological age:

1. Peat: The lowest grade of coal, formed from partially decayed plant matter. It has a high moisture content and low carbon content.
2. Lignite (Brown Coal): A soft, brown, combustible sedimentary rock formed from compressed peat. It has a higher carbon content than peat but is still relatively low.
3. Bituminous Coal (Soft Coal): A dense, black, sedimentary rock. It is the most common type of coal, with a high carbon content and significant volatile matter.
4. Anthracite Coal (Hard Coal): The highest grade of coal, with the highest carbon content and lowest volatile matter. It is hard, shiny, and burns cleanly with little smoke.

Uses of Coal:

1. Electricity Generation: Primarily burned in power plants to generate steam, which drives turbines.
2. Industrial Fuel: Used in industries like cement production and steel manufacturing.
3. Coke Production: Bituminous coal is heated to produce coke, a key raw material in blast furnaces for iron production.
4. Source of Chemicals: Destructive distillation of coal yields coal tar, coal gas, and ammoniacal liquor, which are sources of various organic chemicals.

Gasification and Other Uses of Carbon Compounds

Gasification: This is a process that converts carbonaceous materials (like coal, biomass, or waste) into a gaseous mixture known as synthetic gas (syngas) or producer gas. This is achieved by reacting the material at high temperatures ((>700^circtext{C})) with a controlled amount of oxygen, steam, or carbon dioxide, without combustion.

Other Important Carbon Compounds:

1. Carbon (IV) Oxide (Carbon Dioxide, (text{CO}_2)):
   1. Photosynthesis: Essential for plants to produce food.
   2. Carbonated Drinks: Gives fizzy drinks their bubbles.
   3. Fire Extinguishers: Used to smother fires by displacing oxygen.
   4. Refrigerant: Solid (text{CO}_2) (dry ice) is used for cooling.
2. Carbon (II) Oxide (Carbon Monoxide, (text{CO})):
   1. Fuel: A component of fuel gases like syngas and producer gas.
   2. Reducing Agent: Used in the extraction of metals from their ores (e.g., in blast furnaces).
   3. Chemical Synthesis: Used in the production of various organic chemicals.

   Note: Carbon monoxide is a highly toxic gas that is colourless, odourless, and tasteless. It binds irreversibly to haemoglobin in the blood, preventing oxygen transport.

3. Synthetic Gas (Syngas): A mixture primarily of carbon monoxide ((text{CO})) and hydrogen ((text{H}_2)), often with some carbon dioxide ((text{CO}_2)).
   1. Fuel: Used as a fuel in power generation.
   2. Chemical Feedstock: A crucial raw material for producing methanol, ammonia, and synthetic fuels (e.g., Fischer-Tropsch process).

Teaching Methods/Instructional Techniques

Discussion, Demonstration, Guided Practice, Question and Answer, Explanation, Group Work, Observation.

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Recalling/Engaging

Teacher’s Activity: The teacher greets the students and asks them to name some common elements they know. The teacher then introduces carbon as a very important element found everywhere.

Pupils’ Activity: Pupils respond by naming elements like oxygen, hydrogen, iron, and listen attentively to the introduction.

Learning Point: Introduction to carbon

Step 2: Atomic Properties of Carbon

Time: 10 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher guides students to locate carbon on the Periodic Table and states its atomic number, mass number, and valency. The teacher then guides students to write the electron structure of carbon (2, 4) and explains its tetravalency and ability to form various compounds due to catenation and multiple bonding.

Pupils’ Activity: Pupils locate carbon on the Periodic Table, state its properties, and practice writing its electron structure. They ask questions for clarification.

Learning Point: Carbon’s atomic properties

Step 3: Identifying Carbon Compounds

Time: 10 minutes

Teaching Skill: Group Work/Observation

Teacher’s Activity: The teacher divides students into groups and provides them with samples of carbon-containing materials like charcoal, lime, shells, fruits, etc. The teacher guides them to identify these compounds around them that contain carbon and discuss their observations.

Pupils’ Activity: Pupils work in groups to identify and discuss the carbon compounds in the provided samples and in their environment.

Learning Point: Identification of carbon compounds

Step 4: Allotropes of Carbon

Time: 8 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher defines allotropy and lists the crystalline and amorphous allotropes of carbon, showing samples where available (e.g., pencil lead for graphite, charcoal). The teacher briefly explains the structural differences and properties of diamond and graphite, and mentions the isotopes of carbon.

Pupils’ Activity: Pupils listen, observe the samples, and note down the definition of allotropy and the different allotropes of carbon.

Learning Point: Carbon allotropes and isotopes

Step 5: Types and Uses of Coal

Time: 7 minutes

Teaching Skill: Explanation/Discussion

Teacher’s Activity: The teacher explains the different types of coal (peat, lignite, bituminous, anthracite) based on their carbon content and formation. The teacher then discusses the various uses of coal in society, such as electricity generation and industrial fuel.

Pupils’ Activity: Pupils listen to the explanation and contribute to the discussion on the uses of coal, relating it to their daily lives.

Learning Point: Coal types and uses

Step 6: Other Carbon Compounds and Uses

Time: 5 minutes

Teaching Skill: Explanation/Caution

Teacher’s Activity: The teacher explains gasification and discusses the uses of carbon (IV) oxide ((text{CO}_2)) and carbon (II) oxide ((text{CO})), highlighting the toxicity of carbon monoxide. The teacher also mentions synthetic gas.

Pupils’ Activity: Pupils listen to the explanations, noting the uses and the safety precaution regarding carbon monoxide.

Learning Point: Uses of carbon compounds

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. State the atomic number and valency of carbon.
2. List two crystalline allotropes of carbon.
3. Mention two uses of coal.
4. Why is carbon monoxide dangerous?

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Assessment of understanding

Step 8: Note-Taking

Time: 10 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes on carbon’s properties, allotropes, and uses into their notebooks.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Recording lesson notes

Step 9: Conclusion

Time: 5 minutes

Teaching Skill: Consolidation

Teacher’s Activity: The teacher briefly summarizes the key points of the lesson, emphasizing the versatility of carbon and its importance in both natural and industrial processes. The teacher reminds students of the dangers of carbon monoxide and encourages further reading.

Pupils’ Activity: Pupils listen and ask any final questions.

Learning Point: Lesson consolidation

Continuous Assessment/Further Study

Type: Homework

Instruction: Answer the following questions in your notebook.

1. Explain the term “catenation” as it applies to carbon.
2. Differentiate between diamond and graphite based on their structure and electrical conductivity.
3. List three common substances you use daily that contain carbon.
4. Research and write a short paragraph on the environmental impact of burning coal.
5. Identify the chemical formula for carbon (IV) oxide and state two of its uses.

Lesson Keywords

• Carbon – A non-metallic element, symbol C, atomic number 6.
• Valency – The combining power of an element, carbon has a valency of 4.
• Allotropy – The existence of an element in two or more forms in the same physical state.
• Allotropes – Different structural forms of the same element (e.g., diamond, graphite).
• Catenation – The ability of an element to form bonds with atoms of itself, forming chains or rings.
• Coal – A combustible fossil fuel, a type of amorphous carbon.
• Gasification – Process converting carbonaceous materials into synthetic gas.
• Carbon monoxide – (text{CO}), a toxic carbon compound.
• Carbon dioxide – (text{CO}_2), a common carbon compound essential for photosynthesis.

Differentiation

For learners needing support: Provide simplified diagrams of carbon’s electron structure and allotropes. Pair them with more advanced learners during group activities. Focus on identifying and listing key terms and properties. Provide a glossary of terms.

For advanced learners: Challenge them to research other allotropes of carbon (e.g., fullerenes, nanotubes) and their applications. Ask them to explain the hybridization of carbon in diamond and graphite in more detail. Encourage them to explore the role of carbon in the carbon cycle.

Suggested Lesson Videos

Search on YouTube for: “Carbon and its compounds SS1 Chemistry Nigeria” or “Allotropes of Carbon explained for secondary school”