Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Seperate Chemistry > Flashcards

Seperate Chemistry Flashcards

1
Q

What are alkanes?

A
  • Alkanes are part of a homologous series called hydrocarbons that all have similar chemical structures
  • they are saturated hydrocarbons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the first 6 alkanes and how many carbons do they have?

A 
Methane (1)
Ethane (2)
Propane (3)
Butane (4)
Pentane (5)
Hexane (6)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does saturated mean?

A

All they’re bonds have been used up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are alkenes?

A

They are part of a homologous group of hydrocarbons

  • they are unsaturated
  • they have a functional group of C=C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the first 3 alkenes and how many carbons do they have?

A 
Ethene (2)
Propene (3)
Butene (4)
-But-1-ene (C-C-C=C)
-But-2-ene (C-C=C-C)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How can you test for alkenes?

A

Using bromine water as when shaken together, alkenes will de colourise bromine water turning it colourless. This is because an addition reaction takes place where bromine is added across the alkene double bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a functional group?

A

A group of atoms that determine how a molecule reacts

Members of a homologous series all have the same functional group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the general formula for alkanes?

A

CnH2n + 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the general formula for alkenes?

A

CnH2n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do hydrocarbons produce in an oxidation reaction?

A

Carbon dioxide + water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are polymers?

A

Substances of high average relative molecular mass made by joining up lots of small repeating units called monomer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What do monomers that make up addition polymers have and what is addition polymerisation?

A

A double Covalent bong
-lots of unsaturated monomer molecules can open in their double bond and join together to form polymer chains -this is addition polymerisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do you write the new name of that polymer?

A

Poly(monomer)

E.g. poly(propene)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do you draw the displayed formula of a addition polymer?

A
  • join the carbons together in a row with no double bonds between them
  • stick a pair of brackets around the repeating unit
  • put an n after the pair of brackets
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the properties and used of poly(ethene) and poly(propene)?

A
  • poly(ethene)=flexible, electrical insulator and cheap= used for plastic pads, bottles and wire insulators
  • poly(propene)=flexible, strong, tough and mouldable -used for crates, furniture and ropes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the properties of poly(chloroethene) and poly(tetrafluroethene)?

A 
PVC = tough and cheap =used for window frames and water pipes
PTFE = unreactive, tough and non-stick =nostick pans and waterproof clothing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is condensation polymerisation?

A
  • when we react a dialcohol with a dicarboxylic Acid
  • each monomer must contain two functional groups
  • for each new bond formed a small molecule like water is lost
  • forms a polyester
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a condensation reaction?

A

A carboxylic Acid and an alcohol react to form an Ester link and a small molecule like water is lost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How do you turn a polymer diagram into a monomer diagram?

A
  • take away the brackets
  • do not draw the (n)
  • draw the same molecule but with a double bond between the carbons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Other than an Ester, What is also made through a condensation polymerisation reaction?

A

Water

-the OH from the carboxylic Acid and the H from the alcohol are eliminated to make water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are some naturally occurring polymers

A
  • DNA = nucleotides are the monomers
  • starch = sugar are the monomers
  • proteins = amino acids are the monomers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do we dispose of polymers through landfill sites?

A
  • lots of plastic made up of different polymers is dumped in landfill sites as it is too difficult or expensive to separate
  • valuable land is used and the surroundings become polluted as most polymers are non-biodegradable so cannot be broken down
  • there is also a shortage of land to carry this process out
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are some advantages of disposing polymers through combustion?

A

-gives of heat which can be transferred to generate electrical energy which is an easy quick way of getting energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are some disadvantages of disposing of polymers through combustion?

A
  • gives off harmful greenhouse gases such as carbon dioxide which contribute to global warming
  • sulphur dioxide is given off which can create acid rain and damage ecosystems
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the advantages of recycling polymers?

A
  • reduces the amount of non-biodegradable waste in landfill sites
  • reduces emission of greenhouse gases from burning polymers
  • uses less energy resources than making new plastics
  • saves money and creates jobs
26
Q

What are some disadvantages of recycling polymers?

A
  • polymers must be separated which is expensive and difficult
  • if polymers are mixed together the quality of the final recycled polymer will be reduced
  • can only be recycled a finite number of times
  • can release dangerous gases that may harm our environment
27
Q

What is the functional group of alcohols?

A

-OH

and they always have an -ol on the end of their name

28
Q

What us the general formula for alcohols?

A

CnH2n+1 OH

29
Q

What are the first 4 alcohols and how many carbons do the contain?

A

Methanol (1)
Ethanol (2)
Propanol (3)
Butanol (4) = C4H9OH

30
Q

What do alcohols do?

A
  • undergo complete combustion
  • all can be oxidised to form carboxylic acids
  • react with metals to form hydrogen gas
31
Q

Whatcus the functional group of carboxylic Acid?

A

-COOH
They all end in -oic Acid
-the o is double bonded in the functional group

32
Q

What is the general formula for carboxylic acids?

A

CnH2n+1COOH

33
Q

What are the first 4 carboxylic acids?

A 
Methanol Acid (1) e.g. HCOOH
Ethanoic acid (2)
propanoic Acid (3)
Butanoic Acid (4)
34
Q

What is fermentation?

A

Ethanol can be made through fermentation

  • fermentation is the process of using yeast to convert a type of carbohydrate called sugars into alcohol
  • the products are ethanol and carbon dioxide
35
Q

What are the first 2 steps of fermentation to create ethanol?

A
  • mix yeast and a solution of a carbohydrate, seal the container and leave in a warm place (between 30 and 40° as fermentation happens fastest at these temperatures
  • make sure the conditions are anaerobic (no oxygen) as otherwise you create ethanoic acid
36
Q

What are the 3 and 4th stages of fermentation to create ethanol?

A
  • when the concentration of alcohol reaches 10-20% stop the reaction in order not to kill the yeast
  • the yeast should fall to the bottom of the container so collect the ethanol solution from the top.
37
Q

How do you make a concentrated solution of ethanol as fermentation produces a dilute version?

A
  • through fractional distillation as ethanol has a lower boiling boing than water so will evaporate quicker than water to be separated
  • a Liebig condenser is used to condense ethanol
38
Q

Why do countries with no oil deposits but plenty of land and sunshine use alcohol as a fuel?

A

As they have the right conditions to grow sugar cane which can be fermented into ethanol and then used as a fuel for cars

39
Q

What are the first 3 stages of burning ethanol to heat up water?

A
  • but alcohol into a spirit burner and measure the mass of the burner using a mass balance
  • measure 100cm3 of distilled water into a copper calorimeter
  • insulate the calorimeter by using a drought excluder and then cover with an insulating lid with a thermometer inside (makes sure minimal energy is lost)
40
Q

What are the 4th and 5th stages of burning alcohol to heat up water?

A
  • take the initial temperature of the water and then place it under the calorimeter
  • stir the water throughout using the thermometer and when the water reaches 20° blow the spirit burner out
41
Q

What are the 6th and 7th stages of burning alcohol to heat up water?

A
  • immediately remeasure the burner and fuel
  • repeat the experiment with other alcohols but keep control variable the same
  • the less alcohol burnt means it is a better fuel
42
Q

What are nanoparticles?

A

Tiny particles made of a few hundred atoms

They have high surface area to volume ratios

43
Q

What can nanoparticles be used for?

A
  • cosmetics such as sun cream as they provide better protection and don’t leave white marks on your skin
  • nano-medicines as tiny fullerenes are absorbed easily by the body so could deliver drugs to the right cells
  • lubricant coatings
44
Q

What are the properties and uses of polymers?

A
  • very flexible so can easily be moulded into shapes
  • they’re often cheap and not dense so are suitable for packaging
  • they are thermal and electrical insulators
45
Q

What are the properties and uses of ceramics?

A
  • thermal and electrical insulators
  • strong and hard wearing so good for building e.g. clay
  • don’t degrade or corrode easily so can last long so we use glass for example in windows rather than plastic
  • e.g. clay and glass
46
Q

What are the properties and used of metals?

A
  • thermal and electrical conductors
  • malleable so can be used for a variety of shapes and sizes
  • some are corrosion resistant so last a long time
  • less brittle than ceramics so are less likely to shatter
47
Q

What are the properties and uses of composites?

A

-made through carbon fibres or nanotubes which are expensive but very string and light making them useful for aerospace and car manufacturing
E.g. fibre glass and concrete
-made from one material embedded in another so properties vary and can be designed for certain purposes

48
Q

Why can alcohols be used as fuels?

A
  • they can be used because when they are burnt they release energy
  • a more efficient alcohol fuel is one which is burnt less (longer chained carbon)
49
Q

Why are carbon nanotubes very strong?

A

They have high tensile strength due to their cyclical structure

  • this makes it difficult for atoms to slide
  • it is also made of strong covalent bonds between atoms that require a lot of energy to break apart
  • can do cuts electricity as has free electrons
50
Q

What is corrosion, rusting and tarnishing?

A

Corrosion is when a metal is continually oxidised becoming weak and starts to break down caused by redox reactions

  • tarnishing is when a thin layer of oxide is formed over a metal that prevents further oxidation
  • rusting is the corrosion of iron or steel
51
Q

What is sacrificial protection as a way of preventing rusting?

A

Sacrificial protection involves placing a more reactive metals with the iron so it reacts in place of the metal
E.g. galvanising is an example where zinc is used

52
Q

How do you prevent rusting through the exclusion of oxygen and water?

A
  • removal air involves storing them in an unreactive atmosphere
  • removal of water uses desiccant powder to absorb water
  • barriers might also be used like painting or oiling for moving parts
53
Q

What is electroplating?

A
  • coating the surface of a metal with another metal through electrolysis-the metals used are often unreactive so don’t corrode easily
  • cathode is the objects being electroplated and the anode is the bar of metal you are using
  • electrolyte is solution containing metal ions of the metal your plating
54
Q

What are some uses of electroplating?

A
  • household objects like cutlery and cooking utensils as they are used daily and washed so this stops them corroding
  • jewellery and decorative items to enhance their appearance with metals like gold and silver which are shiny and attractive
55
Q

How does a chemical cell?

A
  • two separate metal electrodes dipped into a solution of one of their own salts
  • a salt bridge allows dissolved ions to pass from one solution to another
56
Q

What is a chemical cell?

A

A device that produces a voltage due to the reactions between chemicals stored in it until one of the reactants has been used up
-more reactive metal is always the cathode

57
Q

What is a fuel cell?

A

An electrical cell that’s supplied with a fuel and oxygen and uses energy from the reaction between them to produce energy efficiently

58
Q

What is a hydrogen-oxygen fuel cell?

A

-e.g. hydrogen + oxygen — Water
(supplied with fuel from air to stop them running flat)
-hydrogen looses electrons at anode which travels to the cathode, oxygen gains electrons at the cathode

59
Q

What are the advantages of hydrogen-oxygen fuel cells?

A
  • more efficient (greater than 80%) than power stations or batteries as energy generated directly and not many stages so less opportunity for energy loss through heat
  • no moving parts so no energy loss through friction
  • doesn’t produce harmful pollutants
  • enhance aerodynamics so quieter
  • hydrogen could be got from hydroelectric power
60
Q

What are the disadvantages of hydrogen-oxygen fuel cells?

A
  • hydrogen is a gas so takes up more space to store and is expensive to store as mist be in reinforced pressurised containers
  • it’s very explosive and flammable so would be dangerous in a car accident
  • hydrogen is made from hydrocarbons or by electrolysis of water which is expensive as requires electricity and produces gases

Chemistry (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions