Chemical Reactivities and Uses of Metals | Chemistry for JAMB PDF Download

Comparison of the Chemical Reactivities of Metals

Metals exhibit varying degrees of chemical reactivity, which can be attributed to their positions in the reactivity series. The reactivity series is a ranking of metals in order of their tendency to undergo chemical reactions. The following are key points to understand the reactivity of metals:

• Highly Reactive Metals: Metals like potassium (K), sodium (Na), calcium (Ca), and magnesium (Mg) are highly reactive. They readily react with oxygen, water, and acids, often producing vigorous reactions and releasing hydrogen gas. For example, sodium reacts explosively with water, while calcium reacts with cold water, releasing hydrogen gas and forming metal hydroxides.
• Moderately Reactive Metals: Metals such as zinc (Zn), iron (Fe), and aluminum (Al) exhibit moderate reactivity. They react with oxygen and water but at a slower rate compared to highly reactive metals. Zinc, for instance, reacts with dilute acids to produce hydrogen gas.
• Less Reactive Metals: Metals like copper (Cu), silver (Ag), and gold (Au) are less reactive. They do not readily react with oxygen or water, making them suitable for various applications where corrosion resistance is required.
• Noble Metals: Noble metals, including platinum (Pt) and gold (Au), are extremely unreactive. They exhibit exceptional resistance to corrosion and remain stable even in harsh environments. These metals find applications in jewelry, electronics, and chemical catalysts.

Uses of Metals

Metals possess a wide range of properties that make them indispensable in various applications. Here are some significant uses of metals:

• Iron (Fe): Iron is a widely used metal due to its strength and durability. It is utilized in the construction industry for the production of structural components such as beams, columns, and reinforcement bars. Iron is also a key ingredient in the manufacturing of automobiles, machinery, and appliances.
• Aluminum (Al): Aluminum is valued for its lightweight nature, excellent corrosion resistance, and electrical conductivity. It is extensively used in the aerospace industry for aircraft construction. Additionally, aluminum finds applications in the production of packaging materials, electrical wires, and heat sinks.
• Copper (Cu): Copper is an excellent conductor of electricity and heat. It is widely used in electrical wiring, power generation, and transmission systems. Copper is also utilized in plumbing, roofing, and various electronic devices.
• Zinc (Zn): Zinc is primarily used as a protective coating for iron and steel to prevent corrosion. It is commonly employed in galvanization, where a layer of zinc is applied to the surface of other metals. Zinc also finds application in batteries, alloys, and the production of various chemicals.
• Gold (Au) and Silver (Ag): Gold and silver are highly valued for their aesthetic appeal and resistance to corrosion. They are extensively used in jewelry, currency, and decorative items. Silver is also utilized in photography, mirrors, and electrical contacts.

Conclusion

In conclusion, the reactivity of metals varies based on their positions in the reactivity series. Highly reactive metals such as potassium, sodium, calcium, and magnesium exhibit vigorous reactions with oxygen, water, and acids. Moderately reactive metals like zinc, iron, and aluminum react at a slower rate, while less reactive metals such as copper, silver, and gold do not readily react with oxygen or water. Noble metals, including platinum and gold, are extremely unreactive and resistant to corrosion.