Question

Classify each of the following materials as metal, semiconductor, or insulator: (a) GaN (b) B (c) \(\mathrm{ZnO}\) (d) \(\mathrm{Pb}\)

Short answer

(a) GaN is a **semiconductor**. (b) Boron (B) is an **insulator**. (c) ZnO (Zinc oxide) is a **semiconductor**. (d) Pb (Lead) is a **metal**.

Step-by-step solution

(a) GaN (Gallium nitride)

GaN, or Gallium nitride, is a compound semiconductor made up of Gallium and Nitrogen. Having intermediate conductivity and ability to manipulate its properties, GaN is a well-known material in the semiconductor industry and is typically used in power electronics and LEDs. Therefore, GaN can be classified as a **semiconductor**.

(b) B (Boron)

Boron (B) is a metalloid element, which means it has properties between metals and non-metals. Although it could be considered a semiconductor depending on how it is prepared, pure boron commonly behaves as an insulator due to its poor conductivity. Thus, Boron can be classified as an **insulator**.

(c) ZnO (Zinc oxide)

Zinc oxide (ZnO) is an inorganic compound often used in various applications such as electronics, optics, and even cosmetics. It is an n-type semiconductor material, which means that it conducts electricity through the movement of electrons. Due to its semiconductor properties, ZnO can be classified as a **semiconductor**.

(d) Pb (Lead)

Lead (Pb) is a well-known metallic element with a high density and ductility. It conducts electricity and heat well, being used since antiquity for wires and pipes. Therefore, Lead can be classified as a **metal**.