Key Words

Question 1

Ligind

Answer 1

Molecule or anion with a lone pair of electrons that can form a dative covalent bind with a central metal cation.

Question 2

Pair of optical isomer

Answer 2

2 non superimposable mirror images

Question 3

Electrophile

Answer 3

Positively/ partially positively charged species (no line pair)-can break a double bond

Question 4

Nucleophile

Answer 4

Partially/fully negatively charged species that donates electrons to have a positive charge= forms a covalent bond

Question 5

Year 1 mechanisms

Answer 5

Nucleophilic substitution-reaction with water/hydroxide ions

Electrophilic addition-bromine across a double bond

Question 6

Year 2 mechanisms

Answer 6

Electrophilic substitution-eg swapping a H in a benzene ring

Nucleophilic addition-breaking double O bonds in carbonyls

Question 7

Electron donating group

Answer 7

Pushed onto 2,4,6 positions
Lone pair delocalises into the ring
More reactive than benzene in electro sub

Eg OH and NH_2

Question 8

Electron withdrawing groups

Answer 8

-3,5 positions
Pulls electrons away from group
Less reactive than benzene in electro sub

Eg NO_2

Question 9

Aliphatic

Answer 9

Straight chained, branches or non aromatic rings

Question 10

Alicyclic

Answer 10

Alicyclic compound arranges in a non aromatic ring with side chains

Question 11

Aromatic

Answer 11

Compounds that contain an arene (benzene) ring

Question 12

Co-polymerisation

Answer 12

Mix up of different monomers (more than 2)

Question 13

Thermosetting polymers

Answer 13

Once moulder do not soften again eg tyres

Question 14

Thermoplastic polymer

Answer 14

Becomes pliable/mouldable at a specific temperature and solidified upon cooling

Question 15

Amine

Answer 15

H of NH_2 group replaces by a carbon

Question 16

Amide

Answer 16

N attached to C=O

Question 17

Nitrile

Answer 17

R-CN

Question 18

Lattice enthalpy

Answer 18

1 mole of ionic compound formed from gaseous ions in standard conditions

Question 19

Enthralled of solution

Answer 19

1 mole of solute dissolves in a solvent (water)

Question 20

Enthalpy of ionisation

Answer 20

1 electron removes from each atom in 1 mole of gaseous atoms

Ea is the reverse

Question 21

Enthalpy of formation

Answer 21

1 mole of compound formed from elements in standard states and conditions
(Products)-(reactants)

Question 22

Exothermic

Answer 22

Heat energy transferee to the surroundings (bond making)

Question 23

Endothermic

Answer 23

Heat energy is absorbed from the surroundings (bond breaking)

Question 24

Standard enthalpy of combustion

Answer 24

When 1 mole of substance is completely burned in O2 under standard conditions

Question 25

Standard enthalpy of neutralisation

Answer 25

When acid and base react in standard states to form 1 mole of water

Question 26

Bond enthalpy

Answer 26

Average energy required to break 1 mole of binds in gaseous molecules

Question 27

Trends in group 2

Answer 27

Reactivity increases down the group First ionisation energy decreases Oh increased down the group and alkability increases

Question 28

Ka=[H+]2/[HA] assumptions

Answer 28

HA equilibrium= initial All H+ from HA [H+]=[A-]

Question 29

Buffer assumptions

Answer 29

[weak acid] equilibrium=initial | All conjugate base from salt not acid

Question 30

Buffer Add H+ Add OH-

Answer 30

H+= shift to left | OH-= shift to right to restore H+ Reacts to produce water

Question 31

Examples bidentate liginds

Answer 31

C_2O_42- H_2NCH_2CH_2NH_2

Question 32

Periodicity | Down a group

Answer 32

Atomic radius increases=increased shielding Increase nuclear charge rules out First ionisation energy decreases

Question 33

Periodicity | Across period

Answer 33

Atomic radius decreases Shielding stays the same Higher nuclear charge=strong attraction First ionisation energy increases

Question 34

Qualitative analysis

Answer 34

1-carbonate-dilute nitric acid 2-Sulphate test-add barium 3-halide test-add silver nitrate 4-test for cations-NaOH=produce ammonia gas

Question 35

Primary cell

Answer 35

Non rechargeable Low current Long storage Alkaline based

Question 36

Secondary cells

Answer 36

Rechargeable | Lead-acid nickel-calcium lithium-ion

Question 37

Fuel cells

Answer 37

Fuel react with O_2 Operate continuously Not have to be recharged Hydrogen fuel cell- +1.23V Acid or alkali H_2 +1/2 O_ = H_2O