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Each atom in a chunk of copper contributes one conduction electron. Look up the density and atomic mass of copper, and calculate the Fermi energy, the Fermi temperature, the degeneracy pressure, and the contribution of the degeneracy pressure to the bulk modulus. Is room temperature sufficiently low to treat this system as a degenerate electron gas?

Short Answer

Expert verified

The Fermi energy is 7.04eV, Fermi temperature 81884K, degeneracy pressure is 3.74Pascal.and the bulk modulus is 6.3105atm.

The found temperature is to large from the room temperature.

Step by step solution

01

Given information

We have given,

Every atom in a chunk of copper is contributes one conduction electron.

We have to find the Fermi energy, Fermi temperature and pressure.

02

Simplify

Formula of the Fermi energy is given by,

f=h28m3N蟺痴23

Where, V is volume of the chunk, which is given by,

V=M

Where we know that the one mole of mass of copper is 63.5gand density of the copper is 8.93g/cm3.

Then volume will be,

V=63.5g8.93g/cm3V=7.1cm3V=7.110-6m3

Since it is given that the every atom is give the one electron. then, number of electron for per unit volume will be equal to number of atom in one mole.

Then,

N=6.0221023electron/mole

Mass of the electron =9.110-31kg

Then, the Fermi energy will be,

f=h28m3N蟺痴23f=(6.6310-34J.s)28(9.110-31kg)3(6.02210237.110-6f=7.04eV

Then, the Fermi temperature will be found out by,

f=KBT

Where KBis Boltzmann's constant.

then,

localid="1649951480186" f=(1.3810-23J/K)TT=1.1310-18J1.3810-23J/KT=81884K

03

simplify

The degeneracy pressure can be found as

P=2N5VfP=26.022102357.110-6m3(1.1310-18J)P=3.74pascal

The contribution of the degeneracy pressure to the bulk modulus is given by,

B=2N3VfB=26.022102337.110-6m31.1310-18JB=6.3105atm

The found temperature is very large than the room temperature that is why it is sufficiently low to treat this system as a degenerate electron gas.

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Most popular questions from this chapter

In the text I claimed that the universe was filled with ionised gas until its temperature cooled to about 3000 K. To see why, assume that the universe contains only photons and hydrogen atoms, with a constant ratio of 109 photons per hydrogen atom. Calculate and plot the fraction of atoms that were ionised as a function of temperature, for temperatures between 0 and 6000 K. How does the result change if the ratio of photons to atoms is 108 or 1010? (Hint: Write everything in terms of dimensionless variables such as t = kT/I, where I is the ionisation energy of hydrogen.)

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