Grade 10
  1. Matter and its properties  1.1. States of matter  1.2. Physical and chemical properties of matter  1.3. Classification of substances (elements, compounds, mixtures)  1.4. Changes in Matter (Physical and Chemical Changes)  1.5. Law of conservation of mass and law of definite proportions
  2. Atomic Structure  2.1. Historical development of the atomic model  2.2. Subatomic particles (protons, neutrons, electrons)  2.3. Atomic number, mass number and isotopes  2.4. Electronic Configuration and Energy Levels  2.5. Valency, ion formation and oxidation state
  3. Periodic table  3.1. History and Development of the Periodic Table  3.2. Modern Periodic Law and Periodic Trends  3.3. Groups and Periods in the Periodic Table  3.4. Trends in the Periodic Table  3.5. Metals, non-metals, metalloids and their properties  3.6. Noble gases and their chemical inertness
  4. Chemical bond  4.1. Formation of Chemical Bonds (Octet Rule)  4.2. Ionic Bonding and Properties of Ionic Compounds  4.3. Covalent Bond and Properties of Covalent Compounds  4.4. Metallic bond and its properties  4.5. Molecular geometry and VSEPR theory  4.6. Polarity and dipole moment of molecules  4.7. Intermolecular forces
  5. Chemical Reactions and Equations  5.1. Types of Chemical Reactions  5.2. Writing and balancing chemical equations  5.3. Law of conservation of mass in chemical reactions  5.4. Factors Affecting Chemical Reactions  5.5. Catalysts and their role in chemical reactions  5.6. Exothermic and Endothermic Reactions
  6. Stoichiometry and Chemical Calculations  6.1. Mole concept and Avogadro number  6.2. Molar Mass and Gram-Mole Conversions  6.3. Empirical and molecular formula  6.4. Stoichiometric calculations and chemical yield  6.5. Limiting and Excess Reactants
  7. Acids, Bases and Salts  7.1. Properties and Definitions of Acids and Bases (Arrhenius, Bronsted-Lowry, Lewis)  7.2. pH Scale, pOH, and Indicators  7.3. Neutralization reactions and salt formation  7.4. Strength of Acids and Bases (Strong vs. Weak Acids and Bases)  7.5. Common Acids and Bases in Daily Life  7.6. Salts, their solubility and applications
  8. Metals and Nonmetals  8.1. Physical and chemical properties of metals  8.2. Physical and Chemical Properties of Non-Metals  8.3. Reactivity Series of Metals and Displacement Reactions  8.4. Extraction of metals from ores  8.5. Corrosion, its causes and prevention  8.6. Alloys, their composition and uses
  9. Carbon and its compounds  9.1. Allotropes of Carbon  9.2. Hydrocarbons and their classification (alkanes, alkenes, alkynes)  9.3. Functional groups in organic compounds  9.4. Nomenclature of organic compounds (IUPAC system)  9.5. Isomerism in organic chemistry (structural and geometrical)  9.6. Important organic reactions (combustion, addition, substitution, polymerization)  9.7. Applications of organic compounds in industry and daily life
  10. Environmental Chemistry  10.1. Air Pollution (Sources, Effects and Control)  10.2. Water Pollution (Causes, Effects and Remedies)  10.3. Greenhouse effect and global warming  10.4. Ozone layer depletion and its effects  10.5. Green Chemistry and Its Applications  10.6. sustainable chemistry practice
  11. Thermochemistry  11.1. Heat and Energy Changes in Chemical Reactions  11.2. Exothermic and Endothermic Reactions  11.3. Enthalpy, enthalpy change, and heat of reaction  11.4. Specific heat capacity and calorimetry  11.5. Energy Changes in Combustion Reactions
  12. Electrochemistry  12.1. Electrolytes and non-electrolytes  12.2. Electrolysis and its applications (electroplating, extraction of metals)  12.3. Redox reactions (oxidation and reduction)  12.4. Galvanic cell and electrochemical series  12.5. Corrosion and electrochemical prevention methods
  13. Chemical kinetics and equilibrium  13.1. Rate of chemical reactions and its measurement  13.2. Factors affecting the reaction rate (catalyst, temperature, concentration)  13.3. Reversible and irreversible reactions  13.4. Dynamic equilibrium and equilibrium constant  13.5. Le Chatelier's principle and its applications
  14. Gases and Gas Laws  14.1. Properties of gases and kinetic molecular theory  14.2. Boyle's Law (Pressure-Volume Relation)  14.3. Charles's Law  14.4. Gay-Lussac's Law  14.5. Combined Gas Law and Ideal Gas Law  14.6. Real Gases vs Ideal Gases
  15. Nuclear Chemistry  15.1. Introduction to Radioactivity and Nuclear Reactions  15.2. Types of radioactive decay (alpha, beta, gamma)  15.3. Half-life and applications of radioactive isotopes  15.4. Nuclear fission and fusion reactions  15.5. Nuclear power generation and its environmental impact

Grade 10 → Carbon and its compounds ↓


Allotropes of Carbon


Carbon is a unique element that is capable of forming different structures. These different structures are known as allotropes. The three well-known allotropes of carbon are diamond, graphite, and fullerene. Each allotrope has unique properties and structures that make them attractive in a variety of scientific and commercial applications. Let us take a deeper look at each of these allotropes, exploring their structure, properties, and uses.

Diamond

Diamond is one of the best-known allotropes of carbon. It is renowned for its hardness and its brilliant clarity, making it highly valued for jewelry. However, diamonds have many other practical uses besides being gemstones.

Diamond structure

In diamond, each carbon atom is covalently bonded to four other carbon atoms in a tetrahedral shape. This forms a three-dimensional lattice that is extremely strong and rigid.

        CCC
         , 
          CCC
          ,
          CCC
         ,
        CCC

The strong covalent bonds between atoms are responsible for diamond's exceptional hardness. The absence of any free electrons results in a transparent material that does not conduct electricity.

Properties of diamond

  • Hardness: Diamond is the hardest naturally occurring substance.
  • Transparency: Because of its structure, a diamond is transparent and allows light to pass through it.
  • Thermal conductivity: Diamond has a very high thermal conductivity, making it an excellent heat conductor.
  • Electrical insulation: Diamond is a poor conductor of electricity due to the lack of free electrons.

Uses of diamonds

In addition to its use in jewelry, diamond's hardness makes it valuable for cutting, grinding, and drilling. Industrial diamonds can be used in saw blades, drill bits, and grinding wheels. The high thermal conductivity also makes diamond valuable in certain electronic applications, such as heat sinks and high-performance computer chips.

Lead

Another allotrope of carbon, graphite, is very different from diamond. It is soft and slippery to the touch and is used in a variety of applications where lubrication or conductivity is important.

Structure of graphite

The carbon atoms in graphite are arranged in layers of a hexagonal lattice. Within these layers, each carbon atom is bonded to three others, forming the planes of the hexagonal ring. These planes are held together by weak van der Waals forces, allowing them to slide easily over one another.

        C -- C -- C -- C
        ,
        C -- C -- C -- C
        ,
        C -- C -- C -- C
         ,   
          CCC 

        [van der Waals forces between layers]

The moving electrons between the layers allow graphite to conduct electricity. This is why graphite is a good lubricant and it is also the reason it makes marks on paper when used as pencil lead.

Properties of graphite

  • Softness: Unlike diamond, graphite is soft and can be used as a lubricant.
  • Electrical conductivity: Graphite is a good conductor of electricity because of its free electrons.
  • Thermal conductivity: Graphite has a high thermal conductivity, slightly less than diamond.
  • Layered structure: The layers can be easily separated, which is why pencil lead works.

Uses of graphite

Graphite is commonly used in pencils, where it is often mixed with clay to form "lead". Its ability to conduct electricity makes it useful in batteries and as an electrode in electrochemical cells. It is also used as a lubricant, where wet lubricants are unsuitable.

Fullerenes

Fullerenes are relatively recently discovered among the carbon allotropes. They are composed of carbon atoms arranged in spherical, tubular or ellipsoidal shapes. The most famous fullerene is the buckyball, scientifically known as C 60.

Structure of fullerenes

C 60 molecule forms a closed cage-like structure that resembles a soccer ball, hence the name buckyball, named after the architect Buckminster Fuller, who designed geodesic domes that resembled these structures. In these fullerene structures, carbon atoms are bonded in patterns of hexagons and pentagons.

                CC
               ,
              CCC
             , 
            CCC -- 
             ,
              CCC

Diversity in fullerene structures is important, because carbon atoms can form tubes (nanotubes) and even complex nested shapes.

Properties of fullerenes

  • Stability: Fullerenes are relatively unstable compared to diamond and graphite, but are stable under certain conditions.
  • Conductivity: Some fullerenes can act as superconductors under specific conditions.
  • Solubility: Fullerenes can dissolve in organic solvents, which is a unique property compared to other carbon forms.

Uses of fullerenes

Fullerenes have potential uses in materials science, electronics and nanotechnology. Their unique shape and properties allow them to be used as drug delivery systems, superconducting materials and even as catalysts in chemical reactions.

Comparison of carbon allotropes

All three allotropes of carbon - diamond, graphite and fullerene - reflect the versatility and unique nature of carbon. This diversity in the structures of the same element illustrates the importance of atomic bonding in determining physical properties.

PropertyDiamondLeadFullerenes
StructureTetrahedral, 3D latticeLayered, planarSpherical, tubular
RigidityVery difficultTenderVariables
Electrical conductivityPoorGoodVariables
Thermal conductivityHighHighVariables
UseJewelry, cutting tools, heat managementPencil, electrodes, lubricantNanotechnology, electronics, drug delivery

Conclusion

The allotropes of carbon illustrate how a single element can exhibit a wide range of properties depending on its atomic arrangement. From incredibly hard diamond to versatile graphite and fascinating fullerenes, each form has its own unique applications and significance in the world of chemistry and beyond. Understanding these allotropes not only highlights the complexity of chemical bonds and structures, but also emphasizes the creative potential of leveraging these materials for various technological advancements.


Grade 10 → 9.1


U
username
0%
completed in Grade 10

← Prev (9)
Carbon and its compounds
Next (9.2) →
Hydrocarbons and their classification (alkanes, alkenes, alkynes)

Comments 



Allotropes of Carbon

https://www.chemistryelite.com/g10/9.1?ceal=en