Q1: The most abundant metal present in the earth's crust is;

ANS:D - aluminium

Aluminium is a lightweight, silvery-white metal with the chemical symbol Al and atomic number 13. Here's an explanation of aluminium:

1. Abundance: Aluminium is the third most abundant element in the Earth's crust, comprising approximately 8.23% by weight. It is found in various minerals, with bauxite being the primary ore from which aluminium is extracted.
2. Extraction: Aluminium is extracted from its ore, bauxite, through a process called the Bayer process. In this process, bauxite is crushed and dissolved in a solution of sodium hydroxide (NaOH) to produce alumina (Al2O3). The alumina is then electrolytically reduced in a smelting process to produce aluminium metal.
3. Properties:
   • Lightweight: Aluminium is lightweight, with a density approximately one-third that of steel, making it ideal for applications where weight savings are important, such as in the aerospace and automotive industries.
   • Corrosion Resistance: Aluminium has excellent corrosion resistance due to the formation of a thin, protective oxide layer on its surface. This oxide layer prevents further oxidation and corrosion, making aluminium suitable for outdoor and marine applications.
   • Ductility and Malleability: Aluminium is highly ductile and malleable, allowing it to be easily formed into various shapes and sizes. It can be rolled into thin sheets, extruded into complex profiles, or cast into intricate shapes.
   • Good Thermal and Electrical Conductivity: Aluminium exhibits good thermal and electrical conductivity, making it valuable in electrical transmission lines, heat exchangers, and other applications where efficient heat or electricity transfer is required.
4. Applications:
   • Transportation: Aluminium is widely used in the transportation industry for manufacturing aircraft, automobiles, trains, and ships due to its lightweight and strength-to-weight ratio.
   • Packaging: Aluminium is commonly used for packaging materials such as cans, foils, and containers due to its corrosion resistance and recyclability.
   • Construction: Aluminium is used in construction for structural components, windows, doors, cladding, and roofing due to its durability, lightweight, and corrosion resistance.
   • Electrical and Electronics: Aluminium is used in electrical transmission lines, heat sinks, electronic enclosures, and capacitors due to its good electrical conductivity and thermal properties.
5. Recyclability: Aluminium is highly recyclable, with nearly 75% of all aluminium ever produced still in use today. Recycling aluminium requires only 5% of the energy needed to produce primary aluminium, making it an environmentally sustainable material.

In summary, aluminium is a versatile metal with a wide range of applications due to its lightweight, corrosion resistance, ductility, and recyclability. It plays a vital role in various industries, including transportation, construction, packaging, and electrical engineering.