Answer:
1. 1568 J
2. 0 J
3. 1176 J
Explanation:
PE = mgh
(PE = Potential Energy) = (m = mass)(g = gravitational force which is 9.8)(h = height)
1. (3)(9.8)(20) = 1568 J
2. PE = (3)(9.8)(0) = 0 J
3. (5)(9.8)(24) = 1176 J
Lattice energy U(MX2) to calculate
Use Born-Haber(-Fajans) Cycle
http://en.wikipedia.org/wiki/Born%E2%80%...
M(s) + X2 → MX2(s) ΔHf°MX2 = -957 kJ mol^-1
M(s) →ΔHsub(M)→ M(g) ΔHsub = 123kJ mol^-1
M(g) →ΔHIE1(M)→ M^+ + e⁻ 757 kJ mol^-1
M^+→ΔHIE2(M)→ M^2+ + e⁻ 1451 kJ mol^-1
X2 →ΔHBE(X2)→ 2X +153 kJ mol^-1
X + e⁻→ΔHEA(X)→ X^- -313 kJ mol^-1
ΔHfo = U + ΔHsub(M) + IE1 + IE2 + ΔHdissX2 + 2EA1(X)
-957= U + 123 + 757 + 1451 + 153 – 626 = U + 1858
U = -2815 kJ mol^-1 The –ve sign is often dropped
Potassium and sulfur. In their ionic states they are a cation and an anion
I believe it is asexually as a mushroom can produce spores if its the only mushroom for miles. Hope this helps! <span />