Polarisation of ionic compounds

Question 1

polarisation

Answer 1

electron cloud distortion of the ions

Question 1

factors affecting polarisation of anion

Answer 1

• polarising power of the cation
• polarisability of an anion

Question 2

polarising power

Answer 2

ability of a cation to polarise the anion (in other words, ability of the positive ion to make negative ion look weird)

Question 3

polarisability of an anion

Answer 3

tendency of an anion to undergo polarisation
- easy for an anion to look weird (undergo distortion) in presence of a cation
- large anion = very easily distorted
- anion with a big negative charge = polarise easily

Question 4

cation

Answer 4

metal ion

Question 5

anion

Answer 5

non metal ion

Question 6

non metals (anions) in the periodic table

Answer 6

size of anion increases down the group (more shielding) so more covalent character
- ex: group 7: At has the most covalent character

Question 7

metal (cation) in the periodic table

Answer 7

size of cation up the group gets smaller (less shielding) but more covalent character
- ex: group 1 lithium has most covalent character

Question 8

smaller the cation or larger the anion

Answer 8

greater the covalent character of ionic compound

Question 9

greater charge on either cation or anion

Answer 9

greater covalent character of ionic compound

Question 10

greater charge

Answer 10

greater polarising power

Question 11

ionic character

Answer 11

• low positive charge
• large cation
• small anion

Question 12

covalent character

Answer 12

• high positive charge
• small cation
• large anion