To obtain electrons as majority charge carriers in a semiconductor the impurity mixed is:

Question

Question

Answer 1

CONCEPT:

The material which is not a good conductor or a good insulator is called a semiconductor.
For example Silicon
The charge carriers which are present in more quantity in a semiconductor compared to other particles are called the majority charge carrier.
Extrinsic semiconductors are of two types

N-type Semiconductor	P-type Semiconductor
In an n-type semiconductor, pentavalent impurity from the V group is added to the pure semiconductor.	In a p-type semiconductor, trivalent impurity from the III group elements is added as the impurity.
Examples of pentavalent impurities are Arsenic, Antimony, Bismuth, etc.	Trivalent impurities like Aluminium, Indium, and Gallium are added to the intrinsic semiconductor.
The pentavalent impurities provide extra electrons and are termed as donor atoms.	The trivalent impurities added provides extra holes known as the acceptor atom.
Electrons are the majority charge carriers in n-type semiconductors.	The majority of charge carriers in a p-type semiconductor are holes.

EXPLANATION:

In an n-type semiconductor, pentavalent impurity from the V group is added to the pure semiconductor.
Electrons are the majority charge carriers in n-type semiconductors.
Hence, option 4 is correct.