437
Carbon (C) – The Element of Life and the Backbone of Organic Chemistry
1. General Information
- Symbol: C
- Atomic Number: 6
- Atomic Mass: 12.01 u
- Group: 14 (Carbon Group)
- Period: 2
- Block: p-block
- Electron Configuration: 1s² 2s² 2p²
- Valence Electrons: 4
- Phase at Room Temperature: Solid
2. Isotopes of Carbon
| Isotope | Protons | Neutrons | Abundance | Notes |
|---|---|---|---|---|
| ¹²C | 6 | 6 | 98.9% | Stable (most common). |
| ¹³C | 6 | 7 | 1.1% | Stable, used in NMR spectroscopy. |
| ¹⁴C | 6 | 8 | Trace | Radioactive (used in carbon dating). |
3. Allotropes of Carbon
| Allotrope | Structure | Properties | Uses |
|---|---|---|---|
| Diamond | Tetrahedral (3D lattice) | Hard, transparent, non-conductive. | Jewelry, cutting tools, electronics. |
| Graphite | Layered (2D sheets) | Soft, conducts electricity. | Pencils, lubricants, batteries. |
| Graphene | Single-layer of graphite | Strong, lightweight, conductive. | Electronics, composites. |
| Fullerenes (C₆₀) | Spherical (Buckyballs) | Hollow, high strength. | Nanotechnology, medicine. |
| Carbon Nanotubes | Cylindrical tubes | Extremely strong and conductive. | Electronics, materials, space tech. |
| Amorphous Carbon | Disordered structure | Varies in hardness and conductivity. | Activated carbon, carbon black. |
4. Physical Properties
- Color: Black (graphite), Clear (diamond).
- Density:
- Diamond: 3.51 g/cm³
- Graphite: 2.26 g/cm³
- Melting Point: Sublimes at 3,642°C.
- Boiling Point: 4,827°C.
5. Chemical Properties
- Valency: 4 (can form 4 covalent bonds).
- Reactivity:
- At High Temperatures: Reacts with oxygen, producing CO or CO₂.
- Forms Compounds with Hydrogen, Oxygen, and Halogens.
- Combustion:
C + O₂ → CO₂ (Complete Combustion) C + ½O₂ → CO (Incomplete Combustion)
6. Occurrence and Abundance
- Fourth most abundant element in the universe.
- Found in:
- Atmosphere: As CO₂.
- Earth’s Crust: In carbonates (limestone).
- Organic Compounds: In all living organisms (proteins, fats, carbohydrates).
- Fossil Fuels: Coal, oil, and natural gas.
7. The Carbon Cycle
- Key Process: Movement of carbon between the atmosphere, oceans, plants, animals, and fossil fuels.
- Stages:
- Photosynthesis: CO₂ → Glucose (by plants).
- Respiration: Glucose → CO₂ (by animals/plants).
- Combustion: Fossil fuels → CO₂.
- Decomposition: Organic matter → Carbon in soil.
8. Industrial Uses of Carbon
| Application | Description |
|---|---|
| Steel Production | Carbon is a key component in steel alloys. |
| Electronics | Graphene and nanotubes in advanced tech. |
| Energy Storage | Graphite in lithium-ion batteries. |
| Filtration | Activated carbon for water and air purification. |
| Fuel | Coal, oil, natural gas. |
| Medical | Fullerenes and carbon nanotubes for drug delivery. |
9. Important Carbon Compounds
| Compound | Formula | Use |
|---|---|---|
| Carbon Dioxide | CO₂ | Greenhouse gas, used in beverages. |
| Carbon Monoxide | CO | Poisonous gas, produced by combustion. |
| Methane | CH₄ | Natural gas, fuel. |
| Calcium Carbonate | CaCO₃ | Chalk, limestone, antacids. |
| Carbon Tetrachloride | CCl₄ | Used as a solvent (now restricted). |
10. Biological Importance of Carbon
- Basis of Organic Chemistry – Forms the backbone of DNA, proteins, fats, and carbohydrates.
- Essential for Life – Present in all known life forms.
- Carbon Bonds: Can form single, double, and triple bonds with other elements.
11. Safety and Toxicity
- Graphite and Diamond – Non-toxic and safe.
- Carbon Monoxide (CO): Highly toxic, binds to hemoglobin and reduces oxygen transport.
- Carbon Dust (Amorphous Carbon): Can cause lung disease if inhaled in large quantities.
Fun Facts About Carbon:
- Diamonds are formed from carbon under extreme heat and pressure deep within the Earth.
- Graphene is 200 times stronger than steel but incredibly lightweight.
- Carbon dating (using ¹⁴C) can determine the age of ancient fossils and artifacts.
- All living organisms are carbon-based, making it the building block of life.