GK
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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have large atomic mass but small atomic numbers
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do not form compounds
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conduct heat and electricity under certain conditions
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are extremely hard
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Detailed explanation-1: -A substance that will conduct electricity only under certain conditions is called a semiconductor. Many semiconductors contain the metalloid silicon. Metalloid elements have properties of metals and of nonmetals.
Detailed explanation-2: -In the case of semiconductors, as temperature increases, electrons in the valence band acquire sufficient energy to be promoted across the “energy gap” into the conduction band. When this occurs, these promoted electrons can move and conduct electricity.
Detailed explanation-3: -The electrical conductivity of a semiconductor depends on a variety of conditions, including applied voltage or current, or the intensity of the infrared radiation, ultraviolet radiation, or visible light on the surface. This is why semiconductors are used to make photovoltaic systems.
Detailed explanation-4: -Therefore, the Semiconductors conduct heat and electricity.
Detailed explanation-5: -Silicon is a semiconductor and has properties of both metals and nonmetals.