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 → Organic chemistry → Functional Group ↓


Aldehyde and ketone


In the fascinating world of organic chemistry, functional groups are the cornerstone of understanding the properties and reactions of organic molecules. Among the myriad functional groups, aldehydes and ketones are particularly important due to their diverse roles in both biological processes and industrial applications.

Introduction to aldehydes and ketones

Aldehydes and ketones are organic compounds that contain a carbonyl group, which is a carbon atom double bonded to an oxygen atom (C=O). This carbonyl group is highly polar, leading to different chemical properties and reactivities.

Structure of aldehyde and ketone

The structures of aldehydes and ketones revolve around the carbonyl group, but they differ in how the carbonyl group is bonded to the other carbon atoms:

Aldehyde

In aldehydes, the carbonyl group is bonded to at least one hydrogen atom. This can be represented as:

R-CHO

Here, R denotes a hydrocarbon group, which may be an alkyl group such as CH 3 or an aryl group such as C 6 H 5 (phenyl). The simplest aldehyde is formaldehyde (HCHO), where the carbonyl group is bonded to two hydrogen atoms.

H Hey C

Ketones

In ketones the carbonyl group is bonded to two other carbon atoms. This can be represented as:

R 1 -CO-R 2

Here, R 1 and R 2 are hydrocarbon groups, which may be the same or different. A common ketone is acetone (CH 3 COCH 3), which is often used as a solvent.

CH 3 CH 3 Hey C

Nomenclature of aldehydes and ketones

Aldehydes and ketones are named according to specific rules set by the International Union of Pure and Applied Chemistry (IUPAC).

Nomenclature of aldehyde

For aldehydes, the suffix -al is used in the name of the compound. The name is based on the longest carbon chain that includes the carbonyl carbon with the lowest carbon prefix. For example:

  • CH 3 CHO: Ethanal (commonly known as acetaldehyde)
  • HCHO: Methanal (commonly known as formaldehyde)

Nomenclature of ketones

Ketones are named using the suffix -one. The name is based on the longest carbon chain that contains the carbonyl carbon, with the locant indicating the position of the carbonyl group. For example:

  • CH 3 COCH 3: Propan-2-one (commonly known as acetone)
  • C 2 H 5 COCH 3: Butan-2-one

Properties of aldehydes and ketones

Physical properties

Aldehydes and ketones exhibit different physical properties due to the presence of the polar carbonyl group. The polar nature of this group results in dipole-dipole interactions, which affect the boiling and melting points.

  • Boiling point and melting point: These points are usually higher than those of hydrocarbons of similar molecular weight, because dipole-dipole interactions occur. However, these are lower than those of alcohols or carboxylic acids of similar weight, because the latter form hydrogen bonds.
  • Solubility: Aldehydes and ketones with short carbon chains are soluble in water due to hydrogen bonding with water molecules. Solubility decreases when the carbon chain is longer.

Chemical properties

Aldehydes and ketones undergo various chemical reactions, which can be mainly classified into nucleophilic addition and oxidation-reduction reactions.

Nucleophilic addition reactions

The carbonyl carbon in aldehydes and ketones is electrophilic, attracting a nucleophile to form a tetrahedral intermediate. Common reactions include:

  • Addition of hydrogen cyanide: Reaction with hydrogen cyanide gives cyanohydrins.
  • Mixture of Grignard reagents: React with Grignard reagents to form alcohols.

Oxidation reactions

Aldehydes can be easily oxidized to carboxylic acids using oxidizing agents such as potassium permanganate (KMnO 4) or nitric acid (HNO 3). In contrast, ketones are generally resistant to oxidation under mild conditions.

Reduction reactions

Both aldehydes and ketones can be reduced to alcohols. Common reducing agents include lithium aluminum hydride (LiAlH 4) and sodium borohydride (NaBH 4).

Applications of aldehydes and ketones

Aldehydes and ketones play important roles in various industrial applications, pharmaceuticals, and biological processes.

Industrial applications

  • Solvents: Ketones such as acetone are widely used as industrial solvents in paints, coatings, and nail polish removers.
  • Resins and plastics: Aldehydes such as formaldehyde are used in the production of resins such as urea-formaldehyde and phenol-formaldehyde, which are essential for plastics manufacturing.

Pharmaceutical applications

  • Medicinal chemistry: Aldehydes such as benzaldehyde are used to synthesize various pharmaceuticals. They serve as intermediates or starting materials in the synthesis of active pharmaceutical ingredients (APIs).

Biological applications

  • Metabolic processes: Ketones are overlooked as essential metabolic intermediates. Acetone bodies, such as acetoacetic acid and β-hydroxybutyrate, are formed in the liver during fatty acid metabolism and serve as an energy source during fasting.

Conclusion

Aldehydes and ketones, with their distinctive carbonyl groups, remain important in the field of organic chemistry. Their unique properties and reactive nature make them invaluable in both industry and biological systems, underscoring their importance in our daily lives.


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Aldehyde and ketone

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