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The equilibrium fraction of lattice sites that are vacant in silver at 700*C is 2-104 Calculate the ember of vacances per chi meter hoor. The tank pund cu day! and 10:35 g/on, respectively O 1.26 x 10^27 O 1.16x 10^25 O 1.16% 10^19 O 1.26x10^25

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Answer:

Step-by-step explanation:

To calculate the number of vacancies per cubic meter per hour, we can use the following equation:

n = N exp(-Q/RT)

where:

- n is the number of vacancies per cubic meter per hour

- N is Avogadro's number (6.022 x 10^23 atoms/mol)

- Q is the activation energy for vacancy formation (in joules/mol)

- R is the gas constant (8.314 J/mol*K)

- T is the temperature in Kelvin

From the given information, we know that the equilibrium fraction of lattice sites that are vacant in silver at 700°C is 2x10^-4. This means that the number of vacancies per lattice site is also 2x10^-4. We can use this information to calculate the activation energy for vacancy formation:

2x10^-4 = exp(-Q/RT)

ln(2x10^-4) = -Q/RT

Q = -ln(2x10^-4) * R * T

At 700°C (973 K), this gives us:

Q = -ln(2x10^-4) * 8.314 J/mol*K * 973 K

Q = 2.06 eV

Now we can use the equation above to calculate the number of vacancies per cubic meter per hour:

n = N exp(-Q/RT)

n = 6.022 x 10^23 exp(-2.06 eV / (8.314 J/mol*K * 973 K))

n = 1.16 x 10^25 vacancies/m^3/hour

Therefore, the answer is O 1.16x 10^25.