Question

What is the use of silicon Carbide?
A.Semiconductor
B.resistor
C.as a dyeing agent
D.none of these

Answer 1

The only compound of silicon and carbon is silicon carbide $(SiC)$, or carborundum. It is a solid industrial mineral crystalline. Silicon carbide exists naturally in an extremely rare mineral called moissanite. Pure $SiC$ appears colorless and transparent crystal. Silicon carbide is mostly used for its hardness and strength.

Complete answer:
Silicon carbide is widely used in the manufacturing of heating elements, slide bearing, sealing rings, wear parts, heat exchangers. Silicon carbide also has the resistivity necessary to perform as a semiconductor material. Silicon carbide is not only the lightest, but also the hardest ceramic material and has excellent thermal conductivity, low thermal expression and is very resistant to acids.
Silicon carbide devices belong to the semiconductor group. They offer a number of attractive characteristics for high voltage power semiconductors when compared to commonly used silicon. Typical properties of silicon carbide are: high hardness, chemical inertness’, thermal shock resistance. Strength at high temperature ranges, electrical conductivity, high thermal conductivity, low coefficient of thermal expression.
Silicon carbide has the ability to form an extremely hard ceramic substance making it useful for applications in automotive brakes and clutches, and also in bulletproof vests. In addition to retaining its strength at up to $1400^\circ C$, this ceramic exhibits the highest corrosion resistance among all the advanced ceramics.

Note:
Silicon most commonly used semiconductors show some limitations especially in high power applications. A relevant factor in these applications is the bandgap, or energy gap, offered by the semiconductor. To overcome these limitations silicon carbide is used as a semiconductor instead of silicon because it has a wide band gap.