General Properties of Metal and their Extraction | Chemistry for JAMB PDF Download

General Properties of Metals

Metals possess various characteristic properties that distinguish them from non-metals. These properties include:

• Physical State: Most metals are solid at room temperature (with the exception of mercury, which is a liquid).
• Luster: Metals have a characteristic shine or luster when freshly cut or polished.
• Malleability: Metals can be hammered or rolled into thin sheets without breaking.
• Ductility: Metals can be drawn into wires without losing their strength.
• Conductivity: Metals are generally good conductors of heat and electricity.
• High Melting and Boiling Points: Metals typically have high melting and boiling points, making them suitable for various industrial applications.
• Density: Metals are generally dense and have a high weight-to-volume ratio.
• Sonorousness: Metals produce a ringing sound when struck, which is why they are used in the construction of musical instruments.
• Chemical Reactivity: Metals exhibit varying degrees of chemical reactivity, with some being highly reactive (e.g., alkali metals) and others being less reactive (e.g., noble metals).

Extraction Methods for Metals

• Electrolysis: Metals that are highly reactive (e.g., sodium, potassium, calcium, and aluminum) are extracted through the process of electrolysis. This involves the use of electric current to decompose a metal compound into its constituent elements.
• Reduction with Carbon: Less reactive metals (e.g., iron, zinc, lead) can be extracted by reducing their ores using carbon as a reducing agent. The carbon removes oxygen from the metal oxide, resulting in the formation of the metal.
• Reduction by Electrolysis: Metals that are more reactive than hydrogen (e.g., magnesium, sodium, calcium) can be extracted by the process of electrolysis using molten salts or aqueous solutions of their compounds.
• Smelting: Some metals, such as copper and tin, can be extracted by smelting their ores. Smelting involves heating the ore in the presence of a reducing agent to obtain the pure metal.

Relationship between Extraction Methods and Properties

The choice of extraction method for a particular metal is influenced by its specific properties, including reactivity, abundance, and the stability of its compounds. Highly reactive metals require more energy-intensive methods such as electrolysis, while less reactive metals can be extracted using carbon or electrolysis. The stability of metal compounds also determines the method of extraction, as some compounds may be reduced more easily than others.
Understanding the general properties of metals is crucial for determining the most suitable extraction method for each metal, as it allows for efficient and cost-effective extraction processes.

Conclusion

In conclusion, metals possess characteristic properties such as luster, malleability, ductility, conductivity, and high melting points. The extraction methods for metals vary based on their properties, with highly reactive metals requiring electrolysis, less reactive metals being extracted using carbon or electrolysis, and smelting being used for certain metals. Knowledge of these properties and extraction methods is essential for the efficient extraction and utilization of metals in various industries.