Homework1 (1).pdf - MSE 170 Autumn 2020, Homework 1 – Due...

MSE 170 Autumn 2020, Homework 1 – Due at 5pm, Oct 9 th
2.18 The net potential energy between two adjacent ions, E
N
, may be represented by the
sum of the Equations 2.9 and 2.11; that is equation 2.17:
𝐸
𝑁
= −
?
𝑟
+
?
𝑛
Calculate the bonding energy E
0
in terms of the parameters A, B, and n using the
following procedure:
1. Differentiate E
N
with respect to r, and then set the resulting expression equal to
zero, because the curve of E
N
versus r is a minimum at E
0
.
2. Solve for r in terms of A, B, and n, which yields r
0
, the equilibrium interionic
spacing.
3. Determine the expression for E
0
by substituting r
0
in Equation 2.17.
2.27 What type(s) of bonding would be expected for each of the following materials:
brass (a copper zinc alloy), epoxy, barium sulfide (BaS), solid xenon, bronze, nylon, and
aluminum phosphide (AlP)?
3.5 Show that the atomic packing factor is for BCC is 0.68.
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