One of the major uses of alkane is?

Analysis

The question asks for the primary application of alkanes in everyday life and industry. To answer this, we must consider the chemical properties of alkanes, specifically their reactivity and energy content.

Concept Explanation

Alkanes are saturated hydrocarbons with the general formula $C_nH_{2n+2}$. They are characterized by strong carbon-carbon (C-C) and carbon-hydrogen (C-H) single bonds.

1. Combustion: Because alkanes are rich in carbon and hydrogen, they undergo combustion reactions in the presence of oxygen to release a significant amount of heat energy. This makes them excellent fuels.
2. Reactivity: Alkanes are relatively unreactive (often called paraffins, meaning "little affinity") compared to alkenes or alkynes. They do not easily undergo addition reactions, which rules out many industrial chemical synthesis processes like the hydrogenation of oils (which requires unsaturated hydrocarbons).

Step-by-Step Solution

• Option A (Domestic and industrial fuel): Alkanes like methane (natural gas), propane, and butane (LPG) are widely used for cooking and heating. Petrol (gasoline) and diesel, which are mixtures of alkanes, power internal combustion engines. This is their most significant use.
• Option B (Hydrogenation of oils): This process involves adding hydrogen to unsaturated fats (alkenes) to make them saturated. Alkanes are already saturated, so they are not used for this.
• Option C (Textile industries): While some petrochemical derivatives are used in textiles (like synthetic fibers), alkanes themselves are not the primary raw material for the textile industry.
• Option D (Production of plastics): Plastics are typically produced from alkenes (like ethene to make polyethene) through polymerization. Alkanes are generally too stable to undergo polymerization easily.

Conclusion

Based on the chemical properties of alkanes, their high heat of combustion makes them the primary choice for energy production in both homes and factories.

Exam Tip: Whenever you see a question about the uses of alkanes, always associate them with combustion and energy. If the question asks about plastics or hydrogenation, look for alkenes instead!