Consider the following:
1. Silicon
2. Germanium
3. Gallium
Which among the above behave as semiconductors as pure elements?

Answer: [A] Only 1 & 2

Silicon and germanium work as semiconductors in pure elements while gallium and some other elements in Groups III and V work as semiconductor as binary compounds for example: gallium arsenide.

This question is a part of GKToday's Integrated IAS General Studies Module