Undergraduate
  1. General chemistry  1.1. Introduction to Chemistry  1.2. Atomic Structure  1.2.1. Subatomic particles  1.2.2. Atomic Model  1.2.3. Quantum numbers  1.2.4. Electron Configuration  1.2.5. Periodic trends  1.2.6. Isotopes and their applications  1.3. Chemical bond  1.3.1. Ionic bond  1.3.2. Covalent bonds  1.3.3. Metal Bond  1.3.4. Hybridization  1.3.5. Molecular geometry and VSEPR theory  1.3.6. Bond polarity and dipole moment  1.4. Stoichiometry  1.4.1. Mole concept  1.4.2. Empirical and molecular formula  1.4.3. Limiting reactant and excess reactant  1.4.4. Percent Yield and Purity  1.4.5. Dilution calculation  1.5. States of matter  1.5.1. Gas Laws  1.5.2. Matter and Intermolecular Forces  1.5.3. Solid and Crystal Structures  1.5.4. Phase diagram  1.5.5. Plasma and supercritical fluid  1.6. Chemical reactions  1.6.1. Types of Chemical Reactions  1.6.2. Balancing Chemical Equations  1.6.3. Thermochemical reactions  1.6.4. Reaction energy profiles  1.7. Solutions and Mixtures  1.7.1. Concentration units  1.7.2. Syndrome properties  1.7.3. Solubility and Solubility Rules  1.7.4. Henry's Law and Raoult's Law  1.7.5. Partition coefficient  1.8. Chemical equilibrium  1.8.1. Law of mass action  1.8.2. Le Chatelier's principle  1.8.3. Reaction quotient  1.8.4. To use this online calculator for Equilibrium Constant, enter Equilibrium Constant (Eq.) and hit the calculate button. Here is how the Equilibrium Constant calculation can be explained with given input values -> 0.05 = 0.05/0.  1.8.5. Acid-base balance  1.9. Acids and bases  1.9.1. Arrhenius, Brønsted–Lowry, and Lewis definitions  1.9.2. pH and pOH  1.9.3. Acid-base titration  1.9.4. Buffer Solution  1.9.5. Acid-base indicator  1.9.6. Polyprotic Acids and Bases  1.10. Electrochemistry  1.10.1. redox reactions  1.10.2. Galvanic and Electrolytic Cells  1.10.3. Nernst equation  1.10.4. Electrolysis  1.10.5. Faraday's laws of electrolysis  1.11. Thermodynamics  1.11.1. Laws of Thermodynamics  1.11.2. Enthalpy, entropy and Gibbs free energy  1.11.3. Spontaneity of reactions  1.11.4. Thermodynamic cycles (Hess's law, Carnot cycle)  1.12. Kinetics  1.12.1. Rate law and reaction order  1.12.2. Activation Energy and Catalyst  1.12.3. Collision theory  1.12.4. Reaction mechanism  1.12.5. Transition state theory
  2. Organic chemistry  2.1. Structure and relationships  2.1.1. Hybridisation in Carbon Compounds  2.1.2. Resonance and aromatization  2.1.3. Molecular orbitals  2.1.4. Inductive and mesomeric effects  2.2. Hydrocarbons  2.2.1. Hydrocarbons  2.2.2. Alkene  2.2.3. Alkynes  2.2.4. Aromatic compounds  2.2.5. Cycloalkanes and Conformation  2.3. Functional Group  2.3.1. Alcohols and phenols  2.3.2. Ethers and epoxides  2.3.3. Aldehyde and ketone  2.3.4. Carboxylic acids and derivatives  2.3.5. Amin  2.3.6. Esters and amides  2.3.7. Thiols and sulfides  2.4. Stereoscopic  2.4.1. Isomerism in Stereochemistry  2.4.2. Chirality and optical activity  2.4.3. Structural analysis  2.4.4. Diastereomers and Enantiomers  2.5.1. Substitution reactions  2.5.2. Elimination reactions  2.5.3. Addition reactions  2.5.4. Radical reactions  2.5.5. Rearrangement reactions  2.5.6. Pericyclic Reactions  2.6. Spectroscopy and structural analysis  2.6.1. Infrared Spectroscopy  2.6.2. Nuclear magnetic resonance spectroscopy  2.6.3. Mass Spectrometry  2.6.4. UV-visible spectroscopy  2.6.5. X-ray crystallography  2.7. Polymer chemistry  2.7.1. Addition and Condensation Polymers  2.7.2. Polymerization mechanism  2.7.3. Biodegradable Polymer  2.7.4. Conducting and smart polymers
  3. Inorganic chemistry  3.1. Coordination chemistry  3.1.1. Ligands and coordination compounds  3.1.2. Crystal field theory  3.1.3. Molecular Orbital Theory in Coordination Compounds  3.1.4. Jahn–Taylor distortion  3.2. Main Group Chemistry  3.2.1. Alkali and alkaline earth metals  3.2.2. Halogens and Noble Gases  3.2.3. Transition metals and their complexes  3.2.4. Lanthanides and Actinides  3.3. Solid state chemistry  3.3.1. Crystal lattices and unit cells  3.3.2. Defects in solids  3.3.3. Electrical and magnetic properties  3.3.4. Superconductivity  3.4. Bio-inorganic chemistry  3.4.1. Metal ions in biology  3.4.2. Enzymatic reactions with metals  3.4.3. Metal poisoning and detoxification  3.4.4. Metalloproteins and Metalloenzymes
  4. Physical chemistry  4.1. Quantum Chemistry  4.1.1. Wave–particle duality  4.1.2. Schrödinger Equation  4.1.3. Quantum Numbers and Orbitals  4.1.4. Atomic and molecular spectroscopy  4.2. Statistical mechanics  4.2.1. Maxwell–Boltzmann distribution  4.2.2. Partitioning functions  4.2.3. Bose–Einstein and Fermi–Dirac statistics  4.3. Chemical thermodynamics  4.3.1. Gibbs Free Energy  4.3.2. Phase transition  4.3.3. Thermodynamic efficiency  4.4. Surface chemistry  4.4.1. Absorption and Catalysis  4.4.2. Colloids and Emulsions
  5. Analytical Chemistry  5.1. Classical methods  5.1.1. Gravimetric Analysis  5.1.2. titrimeter  5.2. Instrumental methods  5.2.1. Chromatography  5.2.2. Spectroscopy  5.2.3. Electroanalytical methods  5.2.4. X-ray diffraction
  6. Industrial Chemistry  6.1. Petrochemistry  6.2. Chemical engineering principles  6.3. Green Chemistry  6.4. Pharmaceuticals and Drug Synthesis
  7. Biochemistry  7.1. Carbohydrates  7.2. Proteins and enzymes  7.3. Lipids and membranes  7.4. Nucleic acids  7.5. Metabolism and Bioenergetics  7.6. Enzyme kinetics and mechanism

Undergraduate → Industrial Chemistry ↓


Green Chemistry


Green chemistry, also known as sustainable chemistry, is a branch of chemistry that focuses on designing products and processes that reduce the use and production of hazardous substances. Its goal is to create more environmentally friendly and efficient chemical processes. This approach emphasizes waste reduction, the use of safer chemicals, and the prevention of pollution at the source rather than treating waste after it is produced.

Principles of green chemistry

Green chemistry is governed by 12 principles developed by Paul Anastas and John Warner in 1998. These principles serve as a framework for chemists to design safer products and processes. Here they are:

  1. Prevention: It is better to prevent waste than to treat or clean it after it has been generated.
  2. Atom economy: Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product.
  3. Less hazardous chemical synthesis: The design should use and produce materials that are low or no toxic to humans and the environment.
  4. Design of safer chemicals: Chemical products must be designed to perform their intended function while also being as non-toxic as possible.
  5. Safe solvents and excipients: Wherever possible, the use of excipients should be made unnecessary and, when used, they should be made harmless.
  6. Design for energy efficiency: Energy requirements should be minimized, and processes should operate at ambient temperature and pressure wherever possible.
  7. Use of renewable feedstocks: Wherever technically and economically feasible, raw materials should be renewable rather than exhaustible.
  8. Minimize derivatization: Unnecessary derivatization should be minimized or avoided if possible, as this typically requires additional reagents and can generate waste.
  9. Catalysis: Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.
  10. Design for degradation: Chemical products should be designed so that at the end of their function they decompose into harmless degradable products.
  11. Real-time analysis for pollution prevention: Analytical methods need to be further developed for real-time in-process monitoring and control before hazardous substances are formed.
  12. Inherently safer chemicals for accident prevention: Substances and their forms should be selected in such a way that the probability of chemical accidents including explosions, fires and emissions into the environment is minimized.

Applications in industrial chemistry

Green chemistry is used in a variety of industries, including pharmaceuticals, agrochemicals, paints and coatings, plastics, and more. Below are some examples of how the principles of green chemistry are applied in industry:

1. Organic synthesis

In the pharmaceutical industry, the synthesis of complex molecules often involves multiple steps and hazardous chemicals. By applying green chemistry principles such as atom economy and less hazardous synthesis, companies can reduce waste and improve safety.

Traditional Synthesis: A + B -> AB Waste = C Green synthesis: A + B -> AB (minimal by-products)

2. Solvent selection

Many chemical processes traditionally use hazardous organic solvents. In green chemistry, safer solvents such as water or supercritical CO2 can be used to reduce toxicity.

Green Solvent

3. Catalysis

Catalysts are substances that can increase the rate of a reaction without consuming it. Green chemistry emphasizes the use of catalysts over stoichiometric reagents, which can help save resources and reduce waste. For example, the use of enzymes as biocatalysts in industrial processes increases specificity and works under gentle conditions.

4. Renewable feedstock

The use of renewable raw materials is becoming increasingly popular as industries move away from non-renewable petroleum-based resources. One example of this is the production of polylactic acid (PLA) from corn starch, which is a biodegradable plastic alternative.

Traditional plastic: Petroleum -> Plastic Green plastic (PLA): Starch (corn) -> Lactic acid -> PLA (biodegradable)

5. Energy efficiency

Chemical reactions often consume large amounts of energy. Green chemistry encourages carrying out reactions at ambient temperatures and pressures to save energy. One example of this is the use of microwave-assisted synthesis, which can reduce energy use and reaction times.

Study the matter

To understand the real-world impact of green chemistry, let's look at some case studies:

1. Supercritical CO2 in the coffee industry

Traditionally, caffeine is extracted from coffee beans using solvents such as methylene chloride. However, by using supercritical CO2, caffeine can be extracted in a much safer and environmentally friendly way.

Traditional Method: Coffee beans + Methylene Chloride (solvent) -> Decaf Coffee Green Method: Coffee beans + Supercritical CO 2 -> Decaf Coffee
Supercritical CO2 Extraction

2. Bio-based polymers

NatureWorks LLC has pioneered the production of bio-based polymers, polylactic acid (PLA), from renewable resources such as corn. This approach helps reduce the carbon footprint of plastics.

Challenges and future directions

Although green chemistry has enormous potential, it also faces several challenges:

  • Cost: Green methods can sometimes be more expensive than conventional methods, which may be a barrier to their adoption.
  • Technical barriers: Developing green processes that match the efficiency and performance of conventional methods can be technically challenging.
  • Market acceptance: Awareness among consumers and industries about the benefits of green chemistry is critical for widespread adoption.

Conclusion

Green chemistry represents a shift toward more sustainable and environmentally friendly chemical manufacturing processes. By focusing on prevention, efficiency, and the use of safer substances, green chemistry provides a framework for the development of chemical products that contribute to a more sustainable world. As technology advances and awareness grows, the application of green chemistry principles is expected to expand, spurring innovation in the chemical industry.


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Green Chemistry

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