Railway Science (Chemistry-Organic Chemistry)

(Methanol) - Boiling point- 64.7°C, C₂H₆O (ethanol) - boiling point 78.37°C, C4H10O (2 - Butanol), Boiling point - 100°C, C₃H₈O (isopropyl alcohol), boiling point - 82.3 °C , Increasing order of boiling point - CH₄O < C₂H₆O  < C₃H₈O < C₄H₁₀O. Homologous series of alkanes have the same formula, CₙH₂ₙ₊₂.

Carboxylic acid (R-COOH) is an organic compound. Physical Properties - Carboxylic acid molecules are polar due to the presence of two electronegative oxygen atoms, higher boiling point than aldehydes, alcohols, and ketones with the same molecular mass.
Chemical Properties - The α-carbon belonging to a carboxylic acid can easily be halogenated via the Hell-Volhard-Zelinsky reaction (a chemical transformation that involves the halogenation of a carboxylic acid at the α carbon).
Uses - manufacture of soaps, utilized for a variety of reasons in the rubber, leather, and textile industries.

Boiling point depends on intermolecular hydrogen bonding, Thus Alcohols tend to have a higher boiling point than ketones because they have an OH group, unlike carbonyls. The same reason supports the fact that carboxylic acids have even higher boiling points.
The boiling point of organic molecules increases in the order: Alkanes < Alkenes < Alkynes < Haloalkanes < Ether < Ester < Amine < Aldehyde < Ketone < Alcohol < Carboxylic Acid < Amide.

Alkanes are organic compounds that consist entirely of single-bonded carbon and hydrogen atoms and lack any other functional groups. Alkanes have the general formula CₙH₂ₙ+₂ and can be subdivided into the following three groups: the linear straight-chain alkanes, branched alkanes, and cycloalkanes.

Molecular mass (-CH₂ group) - 14 amu. Homologous Series - It is a collection of compounds with the same general formula that differ only in the carbon chain length. For example methane, ethane, propane, butane, etc.

A homologous series is a collection of compounds with the same general formula that differ only in the carbon chain length. Member of the alcohol homologous series - methyl alcohol, ethyl alcohol, propyl alcohol and butyl alcohol. The general formula of the homologous series of alcohols is CₙH₂ₙ+₁OH.

Catenation refers to the property of self–linking atoms of an element into longer chains. It depends upon bond energy, size, and bond length between the atoms of the same element. Example - Carbon, Boron, Sulphur, and Silicon.

The boiling points increase with increasing molecular mass because of increase in the number of carbon atoms and Van der Waals force. Boiling point - the temperature at which vapour pressure of a liquid becomes equal to atmospheric or external pressure.
The boiling point of organic molecules increases in the order: Alkanes < Alkenes < Alkynes < Haloalkanes < Ether < Ester < Amine < Aldehyde < Ketone < Alcohol < Carboxylic Acid < Amide.

Molasses Fermentation - Biological process in which sucrose from molasses is converted into cellular energy that produces ethanol (C₂H₆O) and carbon dioxide. Uses of Ethanol - in paints, lacquers and varnish, household cleaning products, Medicines, Preservatives, and Preparation of organic compounds. Propanol (C₃H₈O) is used in inks, fuels, disinfectants, coatings and dyes. Methane (CH₄) is used in fuel to make heat and light.

Alkenes (CₙH₂ₙ) are the group of compounds having double bonds. Alkene series: Ethene (𝐶₂ 𝐻₄), Butene (C₄H₈), Pentene (C₅H₁₀), Hexene (C₆H₁₂), Heptene (C₇H₁₄), Octene (C₈H₁₆). Alkanes have the general formula of CₙH₂ₙ₊₂ and alkynes have CₙH₂ₙ ₋₂.