(14) solid state IV

Question 1

define ionic radii?

Answer 1

distances between ions which can be measured accurately but needs to fix one ion radius to determine all the others

Question 2

define a Schottky defect

Answer 2

POINT DEFECTS
arise from vacant atomic sites in metallic lattices
stoichiometric and electric neutrality is maintained

Question 3

define a Frenkel defect

Answer 3

POINT DEFECT
arises when there is a significant different in the sizes of cations vs anions
the smaller ion can occupy spaces between larger ions and therefore produce vacant atom sites within the metallic lattice

Question 4

describe polarised ionic bonding

Answer 4

as electronegativity differences between A and B decreases, there is an increase in covalent character

Question 5

define lattice enthalpy

Answer 5

the standard enthalpy change when an ionic lattice is broken apart into its constituent ions within the gaseous state