Question

The positive temperature coefficient of resistance is for
A Carbon
B Germanium
C Copper
D An electrolyte

Answer 1

Hint: Metals are opaque, lustrous elements that are good conductors of heat and electricity. Most metals are malleable and ductile and are, in general, denser than the other elemental substances. Metals can be categorised according to their physical or chemical properties. Categories described in the subsections below include ferrous and non-ferrous metals; brittle metals and refractory metals; white metals; heavy and light metals; and base, noble, and precious metals.

Complete step by step answer
We know that a positive Temperature Coefficient (PTC) is when the resistance of a component rises with temperature, it is said to have a positive temperature coefficient.
In the case of semiconductors and insulators, the number of charge carriers per unit volume n increases with an increase in temperature. Hence, the value of the temperature coefficient of resistivity in semiconductors and insulators is negative.
For metallic conductors, the temperature coefficient of resistance is positive. Hence, copper is a metallic conductor.

So, the correct answer is option C.

Note: In chemistry, a metal is an element that readily forms positive ions (cations) and has metallic bonds. A modern definition of metals is that they have overlapping conduction bands and valence bands in their electronic structure. Metals are placed on the left side of the periodic table; Non-metals are placed on the right side of the periodic table and Metalloids are placed in the middle of the periodic table. Metals have a shiny appearance, non-metals have a dull appearance; however, metalloids have a shiny and dull appearance.