8 Flashcards
1
Q
chem: what is a monomer
A
a molecule that can bond to other monomers to make polymers
2
Q
chem: what type of atom are monomers often
A
they are often alkenes (methane)
3
Q
chem: how strong are the intermolecular forces of attraction in polymers
A
strong
4
Q
Chem: why do polymers have higher melting and boiling points that smaller molecules
A
Because they have stronger intermolecular forces
5
Q
Chem: why do polymers have higher melting and boiling points that smaller molecules
A
Because they have stronger intermolecular forces
6
Q
chem: in polymers are covalent bonds weak or strong
A
they are extremily strong
7
Q
Chem: what are the 2 principles of Le Chateliers Principle
A
- If the conditions change then the posision of equalibrium changes
- If the conditions change then the system responds to counteract the change.
8
Q
Chem: what does equilibrium mean
A
The forward and reverse reactions occur at the same rate in a closed system
9
Q
Chem: for equilibrium, does the amount of products and reactants have to be equal
A
No the only must remain the same, individually
10
Q
Chem: what is dynamic equilibrium
A
It is equilibrium where both froward and backward reactions are still happening, the rates of forward and reverse reactions are the same, concentrations of chemicals do not change and it only happens in a closed system
11
Q
Chem: what is collision theory
A
A theory that for a reaction to occurr particles must collide with enough energy
12
Q
Chem: what explains why reactions happen at different rates
A
Collision theory
13
Q
Chem: what are alkanes
A
They all end in ‘ane’
They are hydrocarbons
There formula is CnH2n+2
14
Q
Chem: what are hydrocarbons
A
They are molecules made up of hydrocarbons
15
Q
Chem: what is crude oil found in
A
Rocks
16
Q
Chem: what are the properties of hydrocarbons
A
Check amd edit
17
Q
Chem: what happens to the position of equilibrium when you increase pressure
A
Shift in the direction of the reaction the produces the fewest gas molecules
18
Q
Chem: what happens to the position of equilibrium when you decrease pressure
A
Shifts toward the reaction the produces the most gas
19
Q
Chem: what happens to the position of equilibrium when you increase concentration of the reactant
A
Shifts the equilibrium position toward the products
20
Q
Chem: what happens to the position of equilibrium when you decrease concentration of the reactants
A
Shifts towards the reactants
21
Q
Chem: what happens to the position of equilibrium when you increase temp
A
Shifts to endothermic
22
Q
Chem: what happens to the position of equilibrium when you decrease temp
A
Shifts to the Exothermic
23
Q
Chem: what is crude oil made of
A
It is a mixture of lots of compounds, many hydrocarbons
24
Q
Chem: what is fractional distillation in relation to crude oils
A
It is the process of separating crude oil into groups of hydrocarbons with similar numbers of carbon atoms, these groups of hydrocarbons are called fractions
25
Chem: what are hydrocarbons with lots of carbon atoms calles
Long chain hydrocarbons
26
Chem: what are hydrocarbons with little amounts of carbon atoms called
Short chain hydrocarbons
27
Chem: what do all organic compounds contain
Carbon
28
Chem: what is the equation for burning hydrocarbons when there is plenty of oxygen
- energy is released
- carbon dioxide and water is produced
29
Chem: what happens when there is not enough oxygen when burning hydrocarbons
Carbon monoxide is produced
30
Chem: what are the properties of heavy fractions of crude oil
- don’t ignite easily
- high boiling points
- low volatility
31
Chem: what is cracking
It is the process of breaking down long chain hydrocarbons into short chain hydrocarbons and alkenes that are more useful, it is thermal decomposition
32
Chem: what is catalytic cracking
Vaporised heavy hydrocarbons are passed over the top of a heated catalyst, this produces alkanes and alkenes, e.g. hexane -> butane + ethane, it is preferred in industry as it produces more useful petrol at lower tamps and pressures.
33
Chem: what is steam cracking
Vaporised heavy hydrocarbons are combined with steam at high temperatures, it produces alkanes and alkanes.
34
Chem: what are some uses of hydrocarbons
- being **starting** materials for chemicals like ethanol
- being combined to make polymers
35
Chem: how does fractional distillation of crude oil happen
- crude oil is vaporised and enters a **fractioning column**
- vapours condense at different points and are collected as fractions at these points
36
Chem: what is diesel oil used in
Cars and trains
37
Chem: what is kerosine used for
Jet fuel
38
Chem: what is heavy fuel oil used for
Fuel on ships and in power stations
39
Chem: what are liquified petroleum gasses used for
Fuels
40
Chem: what is a homologous series
It is a series of compounds that can be represented by a formula
41
Chem: why do alkanes have higher melting and boiling points the larger they are
They have more covalent bonds so there are more intermolecular forces to overcome to changed the state and so more energy is required
42
Chem: What property of bonds do alkenes have
They are unsaturated as they have a double carbon bond
43
Chem: what is a fractioning column
It a piece of equipment used in the fractional distillation of crude oils
44
Chem: what is the general formula of alkenes
45
Chem: are alkenes reactive
Their double carbon bond means they are more reactive that the alkanes
46
Chem: what are the 4 smallest alkenes, in order for smallest to largest
Ethene (2 carbon), propene, butene, pentene(5 carbon)
47
Chem: how many carbon atoms does pentene have
5
48
Chem: what is a functional group
A collection of atoms in an organic molecule that affects its reaction e.g. the functional group I alkenes is the carbon carbon double bond
49
Chem: what is a typical reaction for an alkene
Addition
50
Chem: what happens when alkenes react with oxygen
They combust and it is incomplete combustion so burn with a smoky flame
51
Chem: what happens when alkenes react with water when a nickel catalyst is present
When a nickel catalyst is present
52
Chem: what happens when an alkene reacts with water with a phosphoric acid catalyst present
When a Phosphoric acid catalyst is present
53
Chem: how do you test for alkanes and alkenes
You add the thing you want to test to a bromine water solution and shake, nothing will happen when an alkane is present but the solution will change from orange brown to colourless when an alkene is present
54
Chem: what is the function group of alcohols
-OH
55
Chem: what is the general formula for alchohol
56
Chem: what are the 4 smallest alcohols from smallest to largest
Methanol, ethanol, propanol, butanol
57
Chem: what happens when water reacts with alchohol
They dissolve to give neutral solutions
58
Chem: what happens when alchohol react with sodium
Hydrogen is produced
59
Chem: what happens when alchohol reacts with air
They combust completely
60
chem: what does fermnetation produce
ethanol
61
chem: what is the process of fermnetation
- add yeast to a sugar solution
- reaction occurs
- the reaction gives a cloudy solution of ethanol and carbon dioxide
62
chem: waht are the ideal conditions for fermentation
- 37 degrees
- slightly acidic
- absence of oxygen
63
chem: what is the general formula for carboxylic acids
64
chem: what is the functional group of carboxylic acids
-COOH
65
chem: what type of acid is a carboxylic acid
it is a weak acid as it only partially ionises in water
66
chem: what are the 4 smallest carboxylic acids
methanoic acid, ethanoic adic, propanoic acid, butanoic acid
67
chem: what happens when a carboxylic acid reacts with a carboate
products:
- water
- salt
- CO2
68
chem: what happens when a carboxylic acid reacts with water
they dissolve to give a solution wath an acidic PH
69
chem: what happens when a carboxylic acid reacts with alchohols and an acid catalyst
products:
- an ester
- water
70
chem: what is Addition polymerisation
it is the joining of 2 short chain monomers to form a long chain polymer
71
chem: what are the monomers used in Addition polymerisation and why
alkenes because the double carbon bonds can open and allow multiple alkenes to join together
72
chem: how do you name addition polymers
you start with poly and then put in the name of the monomer
73
chem: what is condensation polymerisation
it is the process of joining together 2 monomers with functional groups producing a polymer and small molecule biproducts such as water usually
74
chem: what is the simplist type of condensation polymerisation
combining 2 monomers with the same functional group
75
chem: what are amino acids
they are organic ocmpunds with 2 different functional groups
76
chem: how can amino acids be combined
through condensation polymerisation
77
chem: when amino acids are combined using condenstation polymerisation what are the products
- a polypeptyide
- water
78
chem: what happens whe one or more polypeptide becomes associated
a macromolecule alos known as a protien is formed
79
chem: what is a covalent bond that forms between the amine and carboxyl groups called
a peptide links
80
chem: what are 3 roles of protiens in the body
- enzymes
- haemoglobin
- antibiodies
81
chem: what are the monomers found in DNA called
nucleotides
82
chem: what are the 4 nucleotides called
- **A**denine
- **T**hymine
- **C**ytosine
- **G**uanine
83
chem: what is the shape of DNA
it is 2 polymer chains arranged in the form of a double helix
84
chem: what are 2 naturally occuring polymers steming from sugars
cellulose, starch
85
chem: what are 3 properties that make good fuel
- high melting and boiling points
- high volatility
- high flamability
86
chem: how do you find if a substance is pure
if it has the exact, correct and specific melting and boiling point
87
chem: what will more impurities in a substance cause
the range of temperatures at which the substance will melt and boil
88
chem: what is a fromulation
they are **mixtures** of chemicals that are designed for a specific function, paint is one example
89
chem: what are the 2 phases of chromatography
- mobile phase, this phase is where the liquid or gas moves and substances are picked up and carried
- stationary phase, this is where the substance does not move
90
chem: in chromatography, if a substance moves far which fase is it attracted to
the mobilephase
91
chem: in chromatography, if a substance dosent move far which fase is it attracted to
the stationary phase
92
chem: what is the test for hydrogen
place a lighted splint near the mouth of a test tube containing the unknown gas, if you hear a **squeaky pop** then hydrogen is present
93
chem: why is the noise heard when testing for hydrogen
because the hydrogen is burning rapidly in the presence of oxygen
94
chem: how do you test for oxygen
- light a splint
- wait for it to go out but still be **glowing**
- movet he splint into the container of gas
- if the splint relights then oxygen is present
95
chem: how do you test for carbon dioxide
- setup a test tube of lime water with a tube that gas can be thread through in it, below the liquid line
- feed the gas through the tube, if the lime water **turns cloudy** then CO2 is present
96
chem: how do you test for chlorine
- insert damp litmus paper into a container of gas
- if the litmus paper bleaches and turns from red to white then chlorine is present
97
chem: what is the flame test
some metal ions can be distinguished based on the colour fo their flame, burning the metal can help to determine what it is
98
chem: with what colour does a posotive lithium ion burn
crimson
99
chem: with what colour does a posotive sodium ion burn
yellow
100
chem: with what colour does a posotive potassium ion burn
lilac
101
chem: with what colour does a posotive calcium ion burn
orange-red
102
chem: with what colour does a posotive copper ion burn
green
103
chem: what happens to some aqueous metal ions when they are reacted with a sodium hydroxide (NaOH) solution
they form insoluable solids called precipitates that (for gcse) are metal hydroxides
104
chem: what 3 metals can be removed from aqueous solutions by reacting them with sodium hydroxide
- calcium
- magnesium
- aluminium
105
chem: **what colour** are calcium, magnesium and aluminium **hydroxide** precipitates and **why**
white (they are not transition metals)
106
chem: what colour precipitate is formed when aqueous **Copper(II)** is reacted with NaOH
blue
107
chem: what colour precipitate is formed when aqueous **Iron(III)** is reacted with sodium hydroxide
brown
108
chem: what colour precipitate is formed when aqueous **Iron(II)** is reacted with NaOH
green
109
chem: how do you test for carbonates
react carbonates with dilute acids to form **carbon dioxide + salt + water**, as the carbon dioxide is produced it can be bubbled into limewater to check if it is indeed carbon dioxide
110
chem: how do you test for halides
- add dilute nitric acid to the solution
- add silver nitrate ions
- the halide will form a precipiatate with the silver ions if it is a halide
111
chem: what is a halide
it is a compoud containing a halogen ion
112
chem: what colour is silver chloride
white
113
chem: what colour is silver bromide
cream
114
chem: what colour is silver iodide
pale yellow
115
chem: what are sulfates
116
chem: how do you test for sulfates
- add dilute hydrochloric acid to a solution to remove carbate ions
- add barium chloride, if sulfates are present then a white precipitate will be formed
117
Chem: what is hydrogenisation
It is the process of combining hydrogen and alkenes to form alkanes
118
Chem: how are alcohols produces with alkenes
Alkene + water (steam) -> alcohol
119
Chem: how are halogenalkanes
Halogen + alkene -> halogenalkanes
120
Chem: what happens when alkenes react oxygen
Alkene + oxygen -> combustion
121
chem: what happens during an alkene addition reaction
their double carbon bonds open up allowing hte carbon atoms to bond with new atoms
122
chem: what is it called when atoms hydrogen atoms are added across a double carbon bond
hydrogenisation
123
chem: what is a hydroxyl group
it is the functional group of alchohols and is -OH
124
chem: what is a carboxyl group
it is the functional group of carboxylic acids and is -COOH
125
Chem: what is the name given to groups of hydrocarbons
Fractions
126
Chem: what type of crude oil fraction makes bad feels
Heavy fractions
127
Chem: over the evolution of the earth how did the gas proportions change
128
Chem: what is an **evaluate** question
A question that requires you to say something is better than another thing.
129
Chem: what 2 pollutants does to incomplete combustion cause
- carbon monoxide
- particulates
130
Chem: how do Sulfur impurities cause an environmental effect
Sulphur impurities are in all fossil fuels, when burned it oxidises forming a toxic gas
131
Chem: how do internal combustion engines cause the production of a toxic gas
Hen fossil fuels are burned at high temps in a confined space nitrogen and oxygen react to form nitrogen oxide which is toxic
132
Chem: what environmental effect does increased levels of particulates cause
Increased global dimming
133
Chem: what environmental effects do both Sulfur and nitrogen oxides have
- when inhaled they cause respiratory issues
- they can react with water to for sulphuric acid and nitric acid that cause acid rain
134
Chem: how do the oceans remove carbon dioxide form the atmosphere
- Carbon dioxide dissolves in the oceans
- when it is in this state it can react with water to give carbon precipitates
135
Chem: how do marine animals remove remove carbon form the atmosphere
Marine animals remove carbonates from the oceans to build their shells and skeletons
136
Chem: how many double bonds do alkenes have
All alkenes only have one double bond
137
Chem: carboxylic acid + alcohol ->
Ester
138
Chem: why can giant ionic compounds counduct
Because the ions are not free to move
139
Chem: what are precipitates (for GCSE)
Metal hydroxides
140
Chem: what is a reference substance in paper chromatoegraphy
It provides an indication of substance presence, they are pure substances run alongside the solution
141
Chem: what is the product of ethanoic acid + ethanol
Ethyl ethanoate (ester) + water
142
Chem: how are esters formed
Ethanol + carboxylic acid
143
Chem: what is the ending for carboxylic acids
oic, ethanoic acid
144
Chem: using flame tests, why might it be hard to test metals in a mixture
Because some colours might overshadow others
145
Chem: what is the pattern of light that an element gives off called
A line spectrum
146
Chem: how do emission spectra work
1. Heat causes an element to give off light
2. Each element gives off a different pattern of light (this is a line spectrum)
3. Not all of the light is visible
4. A prism is used to split the light, spectroscopy
5. The pattern is used to identify different chemichals
147
Chem: what are the aspects of spectrocpscopy
- more accurate
- highly sensitive
- quicker
- small samples
148
Chem: what are the aspects of flame tests
- Cheaper
- Less training
149
Chem: whatvis spectroscopy
The process of splitting light with a prism into a spectrum
150
Chem: what is different about aluminium in the sodium hydroxide tests (when that is in excess)
It dissolves
151
Chem: when you mix chloride ions with silver nitrate and nitric acid what happens
White precipitates
152
Chem: when you mix bromide ions with silver nitrate and nitric acid what happens
Cream precipitates
153
Chem: when you mix iodide ions with silver nitrate and nitric acid what happens
Yellow precipitates
