Spectroscopy and Chromatography Techniques

Vibrational Spectra (IR Spectra)

IR spectroscopy is concerned with the study of absorption of IR radiation (800nm- 1mm), which causes vibrational transition in the molecule. When a gaseous molecule absorbs IR radiation, it produces transition between the vibrational energy levels. The resultant spectrum is called vibrational spectra. The essential requirement for a molecule to produce an IR spectrum is that the dipole moment of the molecule must change during vibration. Thus, a vibrational spectrum

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Carbohydrates, Lipids, and Proteins: Essential Biomolecules

Carbohydrates

Carbohydrates are compounds composed of carbon (C), hydrogen (H), and oxygen (O). Their general formula is Cn(H2O)n. They are derived from polyalcohols, aldehydes (aldoses), and ketones (ketoses).

Classification

  • Monosaccharides: Consist of one molecule, containing 3-7 carbon atoms. They are sweet, soluble, and crystallize (sugars).
  • Disaccharides: Formed by the binding of two monosaccharide molecules.
  • Oligosaccharides: Composed of several monosaccharide molecules (approximately 10-12).
  • Polysaccharides:
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Stoichiometry & Raoult’s Law: Principles and Applications

Determination of Stoichiometric Ratio in a Complex

The distribution method is a widely used technique to determine the stoichiometric ratio of a complex formed between a metal ion and a ligand. This method is based on the principle of partitioning a substance between two immiscible phases, usually an organic solvent and an aqueous solution.

Principle

When a metal ion forms a complex with a ligand, the distribution of the metal ion between the aqueous and organic phases changes. The stoichiometric ratio

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The 18th Century: Scientific Revolution and the Birth of Modern Chemistry

The Age of Enlightenment

The eighteenth century, known as the Age of Enlightenment, saw a wave of new ideas sweeping across Europe. This intellectual movement promoted modernization and a rejection of the Old Regime. Monarchies, influenced by these new ideas, implemented financial and educational reforms. This system of government was characterized as enlightened despotism, aiming to maintain the status quo of class domination and the perpetuation of their economic privileges. Meanwhile, the bourgeoisie,

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Solubility, Polymorphism, HLB Scale, and More in Chemistry

Factors Affecting Gas Solubility in Liquids

Here are the factors that affect the solubility of a gas in a liquid:

Physical Factors

  • Temperature: An increase in temperature generally decreases the solubility of a gas in a liquid.
  • Pressure: An increase in pressure generally increases the solubility of a gas in a liquid.
  • Surface Area: An increase in the surface area of the liquid can increase the solubility of the gas.

Chemical Factors

  • Polarity of the Liquid: Polar liquids tend to dissolve polar gases more
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Solubility, Polymorphism, and Phase Transitions in Chemistry

Factors Affecting Gas Solubility in Liquids

Physical Factors

  • Temperature
  • Pressure

Chemical Factors

  • Polarity of the Liquid
  • Chemical Reactivity
  • Presence of Other Solutes

Thermodynamic Factors

  • Henry’s Law Constant
  • Entropy Change
  • Enthalpy Change

Other Factors

  • Salting Out Effect
  • Complexation
  • Surfactants

Raoult’s Law

Raoult’s Law states that the vapor pressure of a solution is directly proportional to the mole fraction of the solvent in the solution.

Mathematical Expression of Raoult’s Law

Raoult’s Law can be mathematically

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