Paulings rule one and two

Question 1

what is the main point to Paulings rule

Answer 1

the aim is to minimise the anion-anion and cation-cation replusion and increase cation-anion attraction

Question 2

pauling rule 1

Answer 2

“A coordination polyhedron of anions is formed around every cation (and vice-versa)
- it will only be stable if the cation is in contact with an anion.

Question 3

radius lower limit

Answer 3

(r2+r1)^2 = r2^2+r1^2

Question 4

radius ratio

Answer 4

r2/r1

Question 6

Electrostatic Bond Strength (e.b.s.)

Answer 6

mCcation/number of anions bonded

Question 7

anion charge

Answer 7

Σ(m/n) = x

Question 8

calculating anion charge

Answer 8

O2- has a total valency of 2 satisfied by {4 x Ca2+ (1/6)} + {2 x Ti4+ (2/3)}

Question 9

rule 2 : Electrostatic Valence Principle (“Bond Strength”)

Answer 9

for each ion the sum of m/n/ebs balances charge

Question 10

what is an ionic crystal?

Answer 10

Ionic crystals may thus be considered as sets of linked polyhedra.

Question 11

ionic radii

Answer 11

The cation-anion distance is regarded as the sum of the ionic radii.”