Question A quantitative theory of bonding in ionic crystal was developed by Born and Meyer along the following the lines: the total force of the system is taken to be: ae² V-N 7-72 4πεor² F(r) = N- where N is the number of positive - negative ion pairs, A and n are constants determined from experiment and a the Madelung constant which depends on the crystal structure of the solid. 1. Derive an expression of the total potential energy of the ionic crystal and identify the repulsion and the attraction terms. 2. Derive an expression of the equilibrium interatomic distance ro. 3. Derive an expression of the bonding energy U(ro).

The plot below shows bonding energy vs. interatomic separation for two elements. АВ %3D A. Which element would you expect to have a lower melting point? A same can't tell provide a brief justification of your choice. B. Which element would you expect to have a smaller lattice constant? A B same can't tell provide a brief justification of your choice. C. Which element would you expect to have a larger elastic modulus? A B same can't tell provide a brief justification of your choice. D. Which element would you expect to have the highest yield stress? A B same can't tell provide a brief justification of your choice. Bonding energy

QUESTION 10 The lattice energy of CsCl is 633 kJ/mol, the Madelung constant, a, is 1.763, and the Born exponent, n, is 10.7. The ionic radius of Cl- is known to be 1.81 A, e = 1.6 X 10-19 C and NA = 6.02 X 1023 atom/mol. The estimate ionic radius of Cst is: A. 1.69 Å B. 1.81 A C. 3.5 nm D. 3.5 Å

Solve it correctly please. I will rate and review accordingly,

SAMPLE PROBLEMS & SOLUTIONS Example 1: The interacting potential energy between two ions is represented by the following expression: -1.252 5.625 x 10-6 U = ..Eqn(1) r8 Where (r) is the distance in nm (1nm = 10-m) (U) is in kJ Calculate: a) The equilibrium distance ro in nm. b) The minimum bond energy in kJ. c) The maximum interionic force for the bond in kN.

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Update I Review I Constants I Periodic Table Part A e How much dopant is present in 193 kg of semiconductor with a dopant concentration of 2.00 ppm by mass? Express your answer numerically in grams. • View Available Hint(s) Hνα ΑΣφ dopant = g Submit Part B Because of its semiconducting properties, CdS is sometimes used in electronic devices. The band gap energy for CdS is 2.40 eV. What is wavelength of a photon with this energy? Express your answer numerically in nanometers. • View Available Hint(s) nm P Pearson Pearcon Education Inc All righte recenied | Torme of Llce Drivan PolicyI Dormiccions Contact Lle Show All ce Outlin..pdf MacBook Air DII DD F8 F9 F10 F1 F12 F6 F7 ARAR B * & 8 9

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choose True or False for the following