Question

question 1 Calculate the fraction of atom sites that are vacant for silver at 650°C. Assume an energy for vacancy formation of 0.63 eV/atom.

question 2

Calculate the number of vacancies per cubic meter in some metal at 663°C. The energy for vacancy formation is 0.71 eV/atom, while the density and atomic weight for this metal are 6.25 g/cm³ (at 663°C) and 86.84 g/mol, respectively.

m-3

question 3

For an alloy that consists of 76.9 g copper, 118 g zinc, and 4.14 g lead, what are the concentrations of (a) Cu, (b) Zn, and (c) Pb in weight percent? The atomic weights of Cu, Zn, and Pb are 63.54, 65.39, and 207.2 g/mol, respectively.

(a)

wt%

(b)

wt%

(c)

wt%

Answer 1

No Nylo a = No. e fuochas wt tote Qwa 0.63 eV = 0.63x16x 1019 3 - 1.008 x 16'J. Ta 6804273 = 423k - 10027 1.387162 K4 923 2 3.65 x64 3. Not of density A Modar mass Arogodendo - 6.0221023 form forx 6.25 Along? x 100 cm3 m3 86.84 Alma 4.334 x 1028 atom /m²

- Quiet Ma no e bitxl-681614 1.38810-23 x 936 27. a 36 als No. e = 6.50 X 1024 atorms/ m3 wt to = wte of A 60 told not. X tolal ut - 76.9t llot 4014 - 196.3 g wt% ag cu = b) zna 769 x100 ~ 39 It "h 983 gorroil1 % . Po 2 2.11%