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Carbon, silicon and germanium have four ...

Carbon, silicon and germanium have four valence electrons each. These are characterised by valence and conduction bands separated by energy band gap respectively equal to `(E_(g))_(C ), (E_(g))_(Si) and (E_(g))_(Ge)`. Which of the following statements is true?

A

`(E_(g))_(Si) lt (E_(g))_(Ge) lt (E_(g))_(C )`

B

`(E_(g))_(C) lt (E_(g))_(Ge) lt (E_(g))_(Si )`

C

`(E_(g))_(C) gt (E_(g))_(Si) gt (E_(g))_(Ge )`

D

`(E_(g))_(C) = (E_(g))_(Si) = (E_(g))_(Ge )`

Text Solution

Verified by Experts

The correct Answer is:
C
`(E_(g))_(C) gt (E_(g))_(Si) gt (E_(g))_(Ge )`
Among the given elements the band gap of Si and Ge is 5.4 eV, 1.1 eV and 0.7 eV respectively. Hence, option (c ) is correct.
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