topic 2

Question 1

octet rule?

Answer 1

tendency for an atom to lose or gain electrons in order to achieve noble gas electron configuration

Question 2

Ionic bond

Answer 2

strong electrostatic attraction between oppositely charged ions

Question 3

what do ionic compounds form?

Answer 3

giant ionic lattices

Question 4

factors affecting ionic bond strength

Answer 4

ionic charge and ionic radius

Question 5

ionic properties (5)

Answer 5

conduct electricity when molten or dissolved, ions free to move
Hard brittle crystalline
doesn’t conduct when solid - ions fixed in place
insoluble in non polar solvent
soluble inn polar solvents

Question 6

prove ionic solids have charged particles

Answer 6

dissolve KMnO4 onto wet filter paper, place on microscope slide and attach a current
purple MnO4- ions are observed to migrate towards positive terminal

Question 7

Covalent bond

Answer 7

strong electrostatic attraction between shared pairs of electrons and the two nuclei

Question 8

dative bond

Answer 8

a dative covalent bond involves one atom providing both the electrons in the shared pair

Question 9

Mixed bonding

Answer 9

compounds contain both ionic and covalent bonds

NH4Cl

Question 10

Factors affecting covalent bonds length

Answer 10

size of atom

number of pairs of e shared

Question 11

electron deficient atoms

Answer 11

Be, Al, B

Question 12

expanded octets can be….

Answer 12

P
S
Cl
Br

Question 13

biggest repulsion order in shapes of molecules

Answer 13

L.P to L.P repulsion greater than
L.P to B.P repulsion which is greater than
B.P to B.P repulsion

Question 14

polar covalent bond

Answer 14

shared e are drawn to atom with stronger pull on e

Question 15

electronegativity?

Answer 15

ability for an atom to attract bonding in the covalent bond

Question 16

Dipole

Answer 16

difference in electronegativity when polarisation occurs

cation attracts e of the anion

Question 17

what increases polarising power

Answer 17

high charge density

Question 18

electronegativity increases across group bc

Answer 18

increases N.C, constant shielding = increased attraction between valence e and nucleus

Question 19

electronegativity down group decreases bc

Answer 19

increased shielding and increased atomic radius = decreased attraction

Question 20

where do London forces exist

Answer 20

exist between all molecules

Question 21

how do London forces work

Answer 21

random electron movement in molecule to one side of molecule
creates temporary dipole
this temporary dipole created induced dipole for neighbouring molecule
two molecules now attracted

Question 22

what affects L.F

Answer 22

more electrons = more random e movement so bigger dipoles so stronger london forces

increased branching weakens london forces as molecules have less contact points and cant get as close to each other

Question 23

P:D to P;D

Answer 23

attraction between the partially positive and partially negative ends of a molecule

due to polar bonds

Question 24

Hydrogen bonding

Answer 24

attraction between the lone pair of electrons on an O,N or F atom and an electron deficient hydrogen bonded to an O, N or F atom

Question 25

why do alcohols have higher B.P than alkanes

Answer 25

alcohols have H.B, PD:PD bonding and London forces alkanes only london forces

Question 26

boiling point of hydrogen halides

Answer 26

HF highest BP as it has H.B increased BP from HCl to HI due to increased number of electrons creating stronger london forces

Question 27

how many hydrogen bonds does water form

Answer 27

4 HB forming a rigid 3d lattice

Question 28

why can ice float

Answer 28

ice forms an open lattice structure with molecules being further apart in solid state than in liquid ice is less dense so it can float

Question 29

metallic bonding

Answer 29

electrostatic attraction between metal ion and sea of delocalised electrons creating a lattice

Question 30

properties of metallic bonding

Answer 30

good electrical conductor - delocalised e can carry current good thermal conductor - energy transferred to delocalised e that move around rapidly conducting heat High MP Malleable - layers of atoms can slide over each other into different shapes

Question 31

Diamond structure

Answer 31

giant covalent structure with each c having 4 hydrogen bonds

Question 32

diamond properties (3)

Answer 32

hard - network of atoms high mp poor electric conductor as e fixed in place good thermal conductor atoms pass vibrations rapidly along bonds in rigid structure

Question 33

Graphite structure

Answer 33

giant covalent structure each c contains 3 C.B delocalised e form weak london forces between layers

Question 34

graphite properties

Answer 34

soft - weak L.F easily overcome - layers can slide over each other high MP - alot of eneegry to overcome 3 covalent bonds good electrical conductor - delcoalsied e can move throughout

Question 35

allotrope

Answer 35

different forms of the same element

Question 36

fullerene

Answer 36

simple covalent | each c has 3 covalent bonds