Electronics and Communication Engineering - Exam Questions Papers - Discussion
Discussion Forum : Exam Questions Papers - Exam Paper 1 (Q.No. 39)
39.
The specific gravity of tungsten is 13.8 and its atomic weight is 184.0 Assume that there are two free elements per atom. Then the Fermi level or characteristic energy for the crystal in eV will be
Answer: Option
Explanation:
A quantity of any substance equal to its molecular weight in grams is a mole of that substance contains the same number of molecules as one mole of any other substance. This Avogadro's number and equals 6.02 x 1023 molecules per mole. Thus
= 9.03 x 1028 electrons/m3
Since for tungsten the atomic and the molecular weights are the same. Therefore for tungsten
EF = 3.64 x 10-19(η)2/3
= 3.64 x 10- 19(9.03 x 1028)2/3
EF = 7.326 eV.
Discussion:
1 comments Page 1 of 1.
Shagufta shah said:
1 decade ago
What is 3.64?
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