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Calculate the activation energy, QV, for vacancy formation in silver, given that the equilibrium number of vacancies at 1073°K is 3.6 x 1023 m ⁻³. The atomic weight and density (at 1073°K) of silver are, respectively, 107.9 g/mol and 9.5 g/cm3 .

User Baccandr
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Final answer:

To calculate the activation energy, QV, for vacancy formation in silver, use the equation QV = RT ln(Kv/NV), where R is the gas constant and T is the temperature in Kelvin. The equilibrium number of vacancies at 1073°K is given. To find Kv, use the equation Kv = NV/N, where N is the total number of lattice sites. By substituting the values into the equations, you can calculate the activation energy, QV.

Step-by-step explanation:

To calculate the activation energy, QV, for vacancy formation in silver, we can use the equation:


QV = RT ln(Kv/NV)


Where R is the gas constant (8.314 J/mol·K), T is the temperature in Kelvin, Kv is the equilibrium constant for vacancy formation, and NV is the number of vacancies present.


The equilibrium number of vacancies at 1073°K is given as 3.6 x 1023 m -3. To find Kv, we can use the equation:


Kv = NV/N


Where N is the total number of lattice sites.


Given that the atomic weight of silver is 107.9 g/mol and the density at 1073°K is 9.5 g/cm3, we can calculate N using the equation:


N = (density * Na) / (Atomic weight)


Where Na is Avogadro's number (6.022 x 1023 mol-1).


By substituting the values into the equations, we can calculate the activation energy, QV.

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