AS preperation final notes Flashcards
1
Q
When asked for definition involving mass?
A
Weighted mean mass of…
In comparison to 1/12th of the mass of an atom of C 12
2
Q
First IE=
A
Energy required to remove
1 electron from each atom
In 1 mole of gaseous atoms
To form 1 mole of +1 ions
3
Q
Orbital=
A
Region of space which can hold up to 2 electrons with opposite spin
4
Q
Order of subshells
A
1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10, 4p6
5
Q
Acid=
A
Releases H+ ions in solution
Proton donor
6
Q
Base=
A
Compound which neutralises an acid, to form a salt
Proton acceptor
7
Q
Alkali=
A
A soluble base, which releases OH- ions in solution
8
Q
Silver ion
A
AG+
9
Q
Ammonium ion
A
NH4+
10
Q
Zinc ion:
A
Zn 2+
11
Q
Carbonate ion
A
CO3 2-
12
Q
Sulfate ion
A
SO4 2-
13
Q
Nitrate ion
A
NO3 -
14
Q
Phosphate ion
A
PO4 3-
15
Q
Silver chloride =
A
White precipitate
Soluble in dilute and conc ammonia
16
Q
Silver Bromide =
A
Cream precipitate
Soluble in conc ammonia, not dilute
17
Q
Silver Iodide =
A
Yellow precipitate
Not soluble in ammonia
18
Q
Writing an ionic equation:
A
Balanced equation with states
Split all aqueos solutions into ions
Cancel out anything which is aqueous on both sides
Rewrite
19
Q
Sulphate ions test
A
Add Barium chloride
If present white precipitate forms
20
Q
Carbonate ions test:
A
Add dilute Nitric acid, and bubble gas through limewater
If present goes cloudy
21
Q
Ammonium ions test
A
Heat
Damp litmus paper goes blue
22
Q
Ionic bonding=
A
Electrostatic attraction between positive and negative ions
23
Q
Covalent bond=
A
Strong electrostatic attraction between
Shared pair of electrons
And nuclei of bonded atoms
24
Q
Average bond enthalpy=
A
Average enthalpy change that occurs when:
Breaking by homolytic fission of 1 mole of a given type of bond
In molecules of a gaseous species
25
2 BP around central atom:
Linear
| 180
26
3BP around central atom:
Trigonal planar
| 120
27
4 BP around central atom
Tetrahedral
109.5
2 normal bonds and 2 different types of wedges
28
3 BP and 1 LP around central atom:
Pyramidal:
107
1 normal bond, 2 different types of wedges
29
2 BP and 2 LP around central atom
V shaped
104.5
2 normal bonds
30
6 BP around central atom:
Octahedral
90
2 normal, 2 of one type of wedge, 2 of other type of wedge
31
Electronegativity=
Ability of an atom to attract the bonding electrons in a covalent bond
32
Number of particles=
6.02x10^23 x moles
33
Formula involving mass molar mass and moles
Moles = mass / molar mass
34
Finding ratio in water of crystallisation
Find moles of solid
Find moles of water
Find ratio
35
Percentage error=
(Total uncertainty/ value measured) x 100
36
Formula for moles with conc and volume
Moles = concentration x volume
37
How to find volume of gas at rtp
Volume = 24dm^3 x volume
38
Ideal gas equation:
Pressure (Pa) x Volume (M^3) = moles x 8.314 x temp (kelvin)
39
Atmostpheres to pascals =
multiply by 100,000
40
Chlorine features:
Gas, green
41
Bromine features:
Liquid, brown
42
Halogens colour in water:
```
Cl = colourless/pale green
Br = orange
I= Orange
```
43
Halogens colour in hexane:
```
Cl = Green
Br = Orange
I = purple
```
44
Disproportionation reaction =
Oxidation and reduction of the same element
45
Homologous series =
A series of organic compounds having the same functional group
But each successive member differing by CH2
46
Functional group=
A group of atoms responsible for characteristic reactions of a compound
47
3 steps in radical substitution?
Initiation:
Br2 = 2Br@
Homolytic splitting via UV light
Propagation:
Br@ + CH4 = HBr + CH3@
CH3@ + Br2= CH3Br + Br@
Termination:
CH3@ + Br@ = CH3Br
Br@ + Br@ = Br2
CH3@ + CH3@ = CH3CH3
48
Describe Carbon single bond
End on overlap of atomic orbitals, producing a sigma bond
49
Describe a Carbon double bond
Second bond produced by sideways overlap of P orbitals to form a pi bond
Electrons above and bellow plane of atom
50
Stereoisomer=
molecules that have same structural formulae but different arrangements of atoms in space
51
When can E/Z isomerism occur?
Restricted rotation around double bond
| Each C of double bonds has different groups attached
52
How to name E/Z isomerism
Functional groups on opposite sides=E
On same side= Z
Put these in front of name
Functional group= one with highest mass, includes everything bonded directly to nearest atom
53
How to name cis/trans bonding?
When 1 of the groups attached to each side of the double bond is the name
Same side= cis
Different sides= trans
54
Ethene + Hydrogen reaction
= Ethane
| Requires 150 degrees and Ni catalyst
55
Ethene + Bromine=
Di-Bromoethane
56
Ethene + Hydrogen Bromide=
Bromoethane
57
Ethene + H2O=
Ethanol
Water is steam
Phosphoric acid catalyst
58
Electrophile=
An atom (or group of atoms), attracted to an electron rich centre, where it accepts electrons to form a new covalent bond
59
Drawing electrophilic addition
Draw Alkene with Hydrogen bromide bellow, with hydrogen being closer
Hydrogen is delta positive, bromide is delta negative
Draw curly arrow from double bond to hydrogen
Draw curly arrow from covalent bond in Hydrogen bromide, to the Bromide
Draw alkane, but one carbon is missing a hydrogen and C has a positive charge
Draw Bromide ion with lone pair, and a negative charge
Draw curly arrow from lone pair to positive Carbon
Draw molecule
60
Markownikoffs rule
Most likely product of electrophilic substitution is where Hydrogen bonds to C which is attached to the least amount of Carbons
61
Primary alcohol=
Carbon OH is attached to bonded to 1 Carbon
62
Secondary alcohol=
Carbon OH is attached to bonded to 2 Carbons
63
Tertiary alcohol=
Carbon OH is attached to bonded to 3 Carbons
64
Reflux=
Continues boiling and condensing of a mixture, to prevent loss of volatile components
65
Nucleophile=
An electron pair donor
66
How to draw nucleophilic substiution
Draw Halkoalkane, with C being delta + and Halogen being delta -
Draw an OH group with a lone pair and a negative charge
Draw curly arrow from lone pair to delta positive C
Draw curly arrow from Bond between Halogen and C to the halogen
Halogen replaced by OH producing a halide ion
67
Measuring reactivity of haloalkanes
Reagant= silver Nitrate solution
Conditions= Hot water bath and Ethanol as co solvent
Observe time for silver halide precipitate to form
Ionic equations for both steps
Trend iodoethane fastest, chloroethane slowest
Factor strength of C-Halogen bond
Explain why C-Cl is strongest
68
Dehydration of alcohols=
Heat under reflux
Catalyst of conc sulphuric or phosphoric acid used
Double bond formed, water produced
69
Colour change if an oxidation reaction successful?
Red to green
70
How to produce an aldehyde?
Add oxidising agent to primary alcohol
| Gentle heating with distillation
71
What's an aldehyde?
C double bonded to O, and bonded to a H
| Ending = al
72
How to produce a carboxylic acid
Make aldehyde, add more oxidising agent and heat under reflux
73
Carboxylic acid=
C double bonded to an O
And C bonded to an OH
Ends in "oic acid"
74
How to produce a Ketone?
Add oxidising agent to a secondary alcohol
| Heat under reflux
75
Ketone=
Carbon double bonded to O
76
Can tertiary alcohols be oxidised?
No, stays red
77
Esterfication=
Carboxylic acid + alcohol = Ester + water
Heat under reflux and sulphuric acid catalyst
78
Naming an ester:
First words ends in "yl"
Second word ends in "oate"
Longest alcohol C chain determines what's in front of yl
Longest C chain in carboxylic acid goes in front of oate
79
How to find heat change, and enthalpy change?
Heat change (joules) = mass of solution x change in temp x 4.18
To find enthalpy change divide heat change by 1000
and then divide by the amount of fuel used
Units= kJ mol^-1
80
Standard enthalpy change of combustion:
1 mole of substance completely reacts with oxygen
| Under standard conditions-
81
Standard enthalpy change of formation:
1 mole of compound is formed from it's elements
| Under standard conditions-
82
Standard enthalpy change of neutralisation:
:
| Reaction of acid and alkali to produce 1 mole of H2O, under standard conditions-
83
Lattice enthalpy
Formation of 1 mole of an ionic compound, from it's gaseous ions
Standard conditions
84
Atominsation enthalpy:
Formation of 1 mole of gaseous atoms from elements in standard states
Standard conditions
85
Electron affinity
One electron added to each atom of an element to form 1 mole of gaseous 1- atoms
Uses up an electron
86
Born haber cycle:
Start with elements in natural states
Go upwards atomise metal
atomise gas
all ionisation energies
all electron affinitys (worst one goes down)
Reach gaseous ions
Gaseous ions to ionic compound= lattice enthalpy
Elements in natural state to ionic compound = formation
87
Entropy
Measure of organisation
Entropy change (joules) = (Add up all S values of products) - (Add up all values of S values of reactants)
88
Gibbs free energy (negative it can happen)
Enthalpy change - (kelvin x entropy change)
CONVERT DEGREES TO KELVIN BY ADDING 273
CONVERT ENTROPY TO KJ BY DIVING BY 1000
89
Atom economy formula?
Atom economy = mass of atoms of desired products/ mass of atoms in reactants
