Railway Science (Chemistry-Organic Chemistry) (Part-II)

Unsaturated hydrocarbons are those compounds in which carbon atoms are linked together by double or triple bonds. Example - Alkenes (CₙH₂ₙ) and Alkynes (CₙH₂ₙ₋₁).

Carbohydrates are classified on the basis of their behaviour on hydrolysis - Monosaccharides, Oligosaccharides, Polysaccharides (non-sugars). Glucose: Present in sweet fruits, honey and Ripe grapes . It can be prepared from sucrose (Cane sugar) and from starch (C₆ H₁₀ O₅)n .
Fructose: It is an important ketohexose. It is obtained along with glucose by the hydrolysis of disaccharide, sucrose (C₁₂H₂₂O₁₁). It is a natural monosaccharide found in fruits, honey and vegetables. In its pure form, it is used as a sweetner.

Butyric acid (obtained from dairy products). Soaps (Made by boiling fats or oils with suitable soluble hydroxide) are sodium (Hard soaps) or potassium salts (soft soaps) of long-chain fatty acids.
Saponification - Soaps containing sodium salts are formed by heating fat (glyceryl ester of fatty acid) with an aqueous sodium hydroxide solution. Oleic acid (occurs naturally in various animal and vegetable fats and oils), Palmitic acid (obtained from Palm oil) and Stearic acid (obtained from animal and plant fats).

Ethyl alcohol (C₂H6O), also called alcohol, is a clear, colourless liquid and an ingredient in alcoholic beverages like beer, wine or brandy. Propanol (C₃H₈O) is a colourless liquid used as a solvent in the pharmaceutical industry, mainly for resins and cellulose esters.
Butanol (C₄H₁₀O) is a colourless substance used as a solvent, fuel and as an intermediate in chemical synthesis. Methanol (CH₃OH) is known as a wood alcohol that can be used as a renewable energy, marine and auto fuel, and fuel cells.

It is an organic compound that contains a carbonyl group (C=O) bonded to two alkyl or aryl groups. Ketones are formed by the oxidation of secondary alcohols or by the hydration of alkynes. Examples - acetone, methyl ethyl ketone, and cyclohexanone.

Types of Covalent bonds - Single covalent bond : It is formed when two participating atoms share only one pair of electrons. It is denoted by ‘—’. Example : H₂ . Double covalent bond :
When only two pairs of electrons are shared by the two participating atoms, a double bond is formed. It is denoted by ‘=’. Example : O₂ . Triple covalent bond : Three pairs of electrons are shared by the two participating atoms. It is denoted by, ‘≡’. Example : N₂ .

Chemical Formula (C₂H₅OH). Biofuel, which is naturally produced by the fermentation of sugars by yeasts or via petrochemical processes such as ethylene hydration.
Uses - Alcoholic drinks, perfumes. Alkanes are organic compounds that consist entirely of single-bonded carbon and hydrogen atoms and lack any other functional groups.
Example - Methane (CH₄), Ethane (C₂H₆), Butane (C₄H₁₀). Uses - Natural gas (Main constituent - Methane and Ethane), Liquid Petroleum gas (Main constituent - Propane and Butane).

Also called ethanol and grain alcohol. It is a clear, colourless liquid and an ingredient in alcoholic beverages like beer, wine or brandy. Ethanol - A natural byproduct of plant fermentation and can be produced through the hydration of ethylene. Uses - In the paint industry, In the medicinal industry.

General Formula - (CₙH₂ₙ). The unsaturated hydrocarbons which contain one or more triple bonds are called Alkynes (General Formula - CₙH₂ₙ₋₂)

Homologous series - Series of compounds with similar chemical properties and some functional groups differing from the successive members by CH₂. General Formula of Common Homologous Series: Alkanes (CₙH₂ₙ₊₂), Alkenes (CₙH₂ₙ), Alcohols (CₙH₂ₙ₊₁OH), Carboxylic Acids (CₙH₂ₙ₊₁COOH). Examples of alkane homologous series - methane, ethane, propane, butane, etc.