Concept explainers
Gold has
The fraction of atomic sites which are vacant in gold.
Answer to Problem 4.1P
The vacant fraction of atomic sites in gold at
Explanation of Solution
Given information:
At
The number of vacancies is
Final temperature is
Concept used:
Write the expression for the number of vacancies.
Here,
Calculation:
Use FCC lattice parameter for goldas
For
is calculated as follows:
The temperature is given as
Universal gas constant is
Calculate the activation energy for goldusing equation (1) as follows:
Calculate the fraction of vacant atomic sites
by using value of activation energyas follows:
The vacantfraction of atomic sites in gold at
Want to see more full solutions like this?
Chapter 4 Solutions
The Science and Engineering of Materials (MindTap Course List)
- state the no. of atom on a plane having miller indices of 110 in a Bcc unit cellarrow_forwardCalculate the number of vacancies per m3 for gold at 900 C. the energy for vacancy formation is 0.86 eV/atom.arrow_forwardProve that the directional indices of plane [u v w] is perpendicular to miller indices (h k l).arrow_forward
- Presume that a small solid sample of Cr2O3 is held at very low temperature. Assume (in a thought experiment) that it has been heated a little bit, and 30 Cr3+ vacancies form. How many O2- vacancies must form? HINT: Charge neutrality is necessary at equilibrium.arrow_forward1. For some hypothetical metal the equilibrium number of vacancies at 750°C is 2.8×1024?−3. If the density and atomic weight of this metal are 5.60 ? ??3⁄ and 65.6 ?/???, respectively, calculate the fraction of vacancies for this metal at 750°C. 2. Calculate the number of vacancies per cubic meter in iron at 850°C. The energy for vacancy formation is 1.08 eV/atom. The density and atomic weight for Fe are 7.65 g/cm3 and 55.85 g/mol, respectively. Answer both pleasearrow_forwardAu and Ag form a substitutional solid solution. This means that the crystal structure of an Au-Ag alloy consists of Ag atoms substituting for Au atoms in the regular atomic positions of the FCC structure. For an Au-50 wt% Ag alloy, what fraction of the atomic sites does Ni occupy? NA=6.022e23 A. None of the mentioned/ Geen van die genoemde B. 32.31% C. 50% D. 64.61%arrow_forward
- At 660°C the fractional concentration of vacancies in aluminum is 9 × 10-5. The energy for vacancy formation is therefore: a. 0.72 eV b. 1.44 eV c. 0.79 eV d. 0.75 eV e. 0.68 eVarrow_forwardFor a metal Nv and N are as follows Temperature(K) 300 400 500 N(m^-3) 6.0214x10^28 5.9419x10^28 Nv(m^-3) 1.0476x10^17 5.227x10^21 what is the vacancy formation energy Qv and the value of N at T=400k?arrow_forwardα-Co has an hcp structure with lattice spacings of a= 2.51 A0 and c = 4.07 A0, β Co is fcc, with a cubic lattice spacing of 3.55 A0. What is the difference in density between the two forms?arrow_forward
- A piece of titanium metal with a mass of 20.8 g is heated in boiling water to 99.5°C and then dropped into a coffee cup calorimeter containing 75.0 g of water at 21.7°C. When ther equilibrium is reached, the final temperature is 24.3°C. Calculate the specific heat capacity of titanium.arrow_forwardEngineering Material Lecture: The microstructure of a steel consists of 100% coarse perlite. According to this information, it is reported that the steel contains 1.65% C. Is this result correct? Explain by showing on the Fe-Fe3C equilibrium diagram.arrow_forwardUsing the periodic table, predict the charges of the ions ofthe following elements: (a) Ga, (b) Sr, (c) As, (d) Br, (e) Se.arrow_forward
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY