Log In Start studying!

Select your language

Suggested languages for you:
Answers without the blur. Sign up and see all textbooks for free! Illustration

Q12P

Expert-verified
Fundamentals Of Physics
Found in: Page 1273

Answers without the blur.

Just sign up for free and you're in.

Illustration

Short Answer

What is the probability that, at a temperature of T = 300 K, an electron will jump across the energy gap Eg(=5.5 eV) in a diamond that has a mass equal to the mass of Earth? Use the molar mass of carbon in Appendix F; assume that in diamond there is one valence electron per carbon atom.

The probability that an electron will jump across the energy gap in a diamond is 1.28×10-42

See the step by step solution

Step by Step Solution

Step 1: The given data

a) Temperature of the energy state, T = 300 K

b) Value of energy gap, Eg=5.5 eV

c) Mass of Earth, Me=5.98×1024 kg

d) Molar mass of carbon, m = 12.01 g/ mol

e) Assumption that in diamond there is one valence electron per carbon atom

Step 2: Understanding the concept of Fermi energy

The highest energy level occupied by an electron in the valence band at absolute zero temperature is known as Fermi level and the energy of electrons present in that level is known as Fermi energy.

Formulae:

Number of excited atoms in a mass,

Ne=MemNA (i)

where NA=6.02×1023 is called Avogadro’s number.

The probability of an electron to get excited in an insulator,

P=Ne-Eg/kT (ii)

where k=8.62×10-5 eV

Step 3: Calculation of the probability of excitation atoms to jump an given energy band gap

The number of carbon atoms in a diamond, as massive as the Earth, is given by the number of electrons that get excited.

Thus, using equation (i) and equation (ii), the probability for an electron to get excited is given as-

P=MemNAe-Eg/kT =5.98×1024 kg6.02×1023 /mol12.01 g/mole-5.5 eV8.62×10-5 eV/K300 K =1.28×10-42

Hence, the value of the probability is 1.28×10-42.

Most popular questions for Physics Textbooks

Icon

Want to see more solutions like these?

Sign up for free to discover our expert answers
Get Started - It’s free

Recommended explanations on Physics Textbooks

94% of StudySmarter users get better grades.

Sign up for free
94% of StudySmarter users get better grades.