Understanding the Properties and Uses of Metals and Non-Metals

Metals - Properties of Metals

1. Physical Properties:

   • Lustre: Metals have a shiny surface when freshly cut or polished.
   • Malleability: Metals can be hammered or rolled into thin sheets without breaking. Examples: Gold, silver.
   • Ductility: Metals can be drawn into thin wires. Examples: Copper, aluminum.
   • Conductivity: Metals are good conductors of heat and electricity. Examples: Copper, silver.
   • Density and Strength: Most metals have high density and are strong.
   • Sonorous: Metals produce a ringing sound when struck.
   • Hardness: Most metals are hard except for a few like sodium and potassium.

2. Chemical Properties:

   • Reaction with Oxygen: Metals react with oxygen to form metal oxides. For example:
     • $4Na + O_2 \rightarrow 2Na_2O$
     • $2Mg + O_2 \rightarrow 2MgO$
   • Reaction with Water: Metals react with water to form metal hydroxides and hydrogen gas. For example:
     • $2Na + 2H_2O \rightarrow 2NaOH + H_2$
     • $Ca + 2H_2O \rightarrow Ca(OH)_2 + H_2$
   • Reaction with Acids: Metals react with acids to produce hydrogen gas. For example:
     • $Zn + 2HCl \rightarrow ZnCl_2 + H_2$
     • $Mg + 2HCl \rightarrow MgCl_2 + H_2$
   • Reaction with Bases: Some metals react with bases to produce hydrogen gas. For example:
     • $2Al + 2NaOH + 2H_2O \rightarrow 2NaAlO_2 + 3H_2$
   • Displacement Reactions: Metals can displace less reactive metals from their compounds in aqueous solutions. For example:
     • $Zn + CuSO_4 \rightarrow ZnSO_4 + Cu$

Uses of Metals

• Iron: Used in construction (steel), machinery, and automotive industry.
• Aluminum: Used in aircraft, kitchen utensils, and packaging.
• Copper: Used in electrical wiring, plumbing, and electronics.
• Gold and Silver: Used in jewelry and electronics.
• Zinc: Used for galvanizing iron to prevent rusting and in making alloys like brass.

Non-Metals - Properties of Non-Metals

1. Physical Properties:

   • Lack of Lustre: Non-metals do not have a shiny appearance. They are usually dull.
   • Non-Malleable and Non-Ductile: Non-metals are brittle and break easily when hammered or stretched.
   • Poor Conductors: Non-metals are poor conductors of heat and electricity. Examples: Sulfur, phosphorus.
   • Low Density and Strength: Non-metals generally have lower density and are not strong.
   • Non-Sonorous: Non-metals do not produce a ringing sound when struck.
   • Varied States: Non-metals can be solid, liquid, or gas at room temperature. For example, carbon (solid), bromine (liquid), and oxygen (gas).

2. Chemical Properties:

   • Reaction with Oxygen: Non-metals react with oxygen to form non-metal oxides, which are generally acidic in nature. For example:
     • $C + O_2 \rightarrow CO_2$
     • $S + O_2 \rightarrow SO_2$
   • Reaction with Water: Non-metals do not react with water or produce hydrogen gas.
   • Reaction with Acids: Non-metals do not react with acids.
   • Reaction with Bases: Non-metals react with bases to form salts. For example:
     • $Cl_2 + 2NaOH \rightarrow NaCl + NaOCl + H_2O$
   • Displacement Reactions: Non-metals can displace less reactive non-metals from their compounds. For example:
     • $Cl_2 + 2KI \rightarrow 2KCl + I_2$

Uses of Non-Metals

• Oxygen: Essential for respiration and combustion.
• Nitrogen: Used in fertilizers and as a preservative.
• Carbon: Used in making steel, pencils (graphite), and as a fuel (coal).
• Sulfur: Used in making sulfuric acid, rubber, and fungicides.
• Phosphorus: Used in fertilizers, detergents, and matches.

Comparison of Metals and Non-Metals