Pb-Lead

Lead (Pb) is a chemical element with unique physical characteristics and wide-ranging applications, both in its elemental form and in various compounds. 

Physical Characteristics

• Appearance: Lead is a dense, soft, malleable, and ductile metal with a bright luster when freshly cut, which tarnishes to a dull grayish color when exposed to air.
• Density: It has a high density of 11.34 g/cm³, making it one of the heaviest common metals.
• Melting Point: Lead has a relatively low melting point for a metal at 327.5°C (621.5°F).
• Boiling Point: Its boiling point is 1749°C (3180°F).

Applications

• Batteries: The primary use of lead is in lead-acid batteries for vehicles and backup power systems. These batteries exploit lead’s ability to undergo reversible reactions, providing a reliable source of electrical energy.
• Radiation Shielding: Due to its high density and atomic number, lead is effective at blocking X-rays and gamma rays, making it a common choice for protective shielding in medical and industrial radiography equipment, and in construction of radiation therapy rooms.
• Construction Materials: Lead is used in construction for roofing and in pipes. Its malleability allows it to be shaped to fit various architectural needs, although its use in pipes has diminished due to health concerns.

Compounds

• Lead Acetate (Pb(C2H3O2)2): Known as “sugar of lead,” this compound has been used as a sweetener and in the production of lead-based paints, although its use is now limited due to toxicity concerns.
• Lead Oxide (PbO): Used in making lead glass and as a pigment in paints. Lead oxide is also crucial in the production of lead-acid batteries, where it forms part of both the positive and negative plates.
• Lead Sulfide (PbS): Also known as galena, this is the most important lead ore. It’s used in the production of lead and, historically, as a semiconductor material.
• Lead Carbonate (PbCO3): Once used as a white pigment (lead white) in paints, its use has significantly declined due to toxicity concerns.
• Lead Nitrate (Pb(NO3)2): Employed in the production of matches and special explosives and as a heat stabilizer in nylon and polyesters.

Basics on Boron-Wikipedia