ALKENES Flashcards
What is a homologous series
Organic compounds with the same functional group
What is a functional group
Reactive part of an organic molecule: Alkenes: C=C bonds makes them more reactive than an alkane
General formula for alkanes and alkenes
Alkane: CnH2n+2
Alkene: CnH2n
N= no. of carbons
What does combustion produce
Carbon dioxide and water
Why does the combustion of alkenes produce a sootier flame than an alkane
Incomplete combustion producing carbon particulates
Conditions for hydrogenation
Nickel catalyst, 150*C
Conditions for hydration
Phosphoric acid catalyst, Steam 300*C
Testing alkanes and alkenes with bromine water
Alkanes: stay orange-brown
Alkenes: orange brown to colourless (not Clear)
What is hydrogenation?
Saturating the alkene, converting double bonds into single bonds
What is combustion? (Of an alkene)
A chemical reaction where the alkene reacts with oxygen to produce CO2 and H2O and energy
What is hydration? (Of an alkene)
A chemical reaction where water is added to an alkene to form an alcohol, breaks down the double c bond, adds an -OH group to one carbon and a hydrogen atom to the other
What’s a haloalkane
A haloalkane is an organic compound where one or more hydrogen atoms in an alkane are replaced by a halogen atom (fluorine, chlorine, bromine, or iodine).
What are the first four alcohols in the homologous series
Methanol ethanol propanol butanol
What’s the functional group of alcohols
the OH
What ending goes with alcohols
anol
3 main uses of alcohols
Fuels
Solvents
Alcoholic drinks
How to alcohols react with oxygen
Burn well, combust, oxidised to carboxylic acids slowly by mild oxidant agents
Ethanol + oxygen =
(For complete combustion)
Carbon dioxide + water
Ethanol + oxygen=
(For incomplete/partial combustion)
Ethanoic acid + water
How does alcohol react with sodium
Fizzes (producing H2 gas)
Ethanol + sodium =
Sodium ethoxide + hydrogen
Relationship between alcohols solubility and the no. carbon atoms
Alcohols with small carbon chains are soluble in water and form neutral solutions. However, as the number of carbon atoms in the alcohol increases, solubility in water decreases.
How do alcohols react with carboxylic acid
Carboxylic acids react with alcohols in the presence of a concentrated sulfuric acid (H_2SO_4) catalyst to form esters.
Ethanoic acid + ethanol =
Carboxylic acid + alcohol =
Ethyl ethanoate
Ester + H2O
Chemical formulas of glucose
C6H12O6
Fermentation of sugar cane is a method of making alcohol, what conditions are needed
Yeast catalyst
Anaerobic (if O2 is added it forms carboxylic acid)
Temp 30-40 degrees (at lower temp, rate of reaction too slow, higher temps can make yeast denature which stops the reaction)
You can make alcohol by adding Ethene to H2O, what are the conditions
Phosphoric acid catalyst
Steam
300 degrees
What is biofuel
A renewable fuel made from plant material or animal waste
Glucose = ethanol + carbon dioxide is the equation for what
Fermentation of sugar cane
Advantages of using the fermentation method to create alcohol
Renewable
Doesn’t require as much energy
Disadvantages of using the fermentation method to create alcohol
Land for plants instead of crops
Need time for plants to grow
Batch process with multiple steps
Ethanol is aqueous
Meaning of aqueous
Dissolved in water or containing water
Advantages of using the Ethene method to create alcohol
Continuous process: quick
Only one product formed (no waste)
Ethanol is pure
Disadvantages of using the Ethene method to create alcohol
Non renewable (from crude oil)
Requires lots of energy
What’s the functional group of carboxylic acid and what is the word ending
What are the first four carboxylic acids
COOH
oic acid
Methanoic acid, ethanoic acid, propanoic acid, butanoic acid,
What’s the observation and conclusion for the reaction of water and carboxylic acid
Miscible in water (unusual for organic compounds)
Mix with water to form a weakly acidic solution
What’s the observation and conclusion for the reaction of carbonate and carboxylic acid
Fizzing
React with sodium hydrogen carbonate to produce carbon dioxide gas
What’s the observation and conclusion for the reaction of ethanol and carboxylic acid
Aroma
Butyl ethanoate (also in pears) sweet smelling ester is formed
Meaning of miscible
Two substances can mix together to form a homogeneous solution (dissolve into each other without forming separate layers)
Carboxylic acids are ____ acids so partially ______
Weak
Ionise
Functional group of esters and what’s the word ending
COO
alkyl - - oate
Name one ester
Ethyl ethanoate
Polymers are m__________.
They are a formation of _____ _________ molecules from lots of ______ molecules joining together.
Macromolecules
Long chain
Small
What are the two types of polymers and tell me about their products
Addition: with no other products
Condensation: with another small molecule (e.g water) produced as well
What are the three types of structures when talking about polymers?
Monomer structure
Polymer structure
Repeating unit
What must you always do before converting an Alkene into a polymer in an equation
Rearrange the alkene into the correct format
What is thermosoftening?
• individual chains intertwined
• weak forces between chains
• melt and remold
What is thermosetting
• form cross links between chains and held in solid structure
• hard and rigid
• do not soften when heated
What does phenylethene make
Polystyrene
What does chloroethene make
PVC
What does tetrafluoroethene make
PTFE/Teflon
What does methyl 2-cyanopropenoate make
Superglue
What does methyl propenoate make
Perspex
Uses of polystyrene, PVC, Teflon/PTFE, superglue, Perspex
(These are all products of addition polymers)
Polystyrene: insulation, packaging materials
PVC: plumbing pipes, electrical cable insulation
Teflon/PTFE: non stick coatings, Industrial
lubricants
Superglue: bonding materials, medical applications
Perspex: windows, protective screens
Terylene (a polyester) makes what? What’s it used for?
PET
Plastic bottles, containers, clothing fibres
Nylon, Kevlar and amino acids are examples of polyamides. Give the uses of each one
Nylon: clothing fabrics, ropes
Kevlar: bullet proof vests, strong rope
Amino acids: form proteins
Describe a polyester reaction
Dicarboxylic acid and diol join
H20 is removed
Ester link is formed
What do shapes represent in a condensation polymer reaction
Groups of atoms between the functional groups
What’s the functional group of an Ester
COO
Describe a polyamide reaction
Dicarboxylic acid and diamine
Lose H20
Peptide link formed
What’s the functional group for a polyamide reaction?
CONH
What’s the difference between a polyamide reaction and a polyester reaction?
Polyamide: peptide link (CONH)
Polyester: ester link (COO)
What’s the difference between addition and condensation polymers?
Addition polymer doesn’t produce any other products
A carbonate + a carboxylic acid =
A salt, carbon dioxide and water
What’s the monomer and polymer of carbohydrates
M: Glucose
P: Starch and sugar
What’s the monomer and polymer of proteins
M: amino acids
P: polypeptide (polyamide)
4 examples of naturally occurring proteins
Enzymes
Haemoglobin
Antibodies
Body tissues
What are the two groups making up amino acids
Amine group
Carboxylic acid group
What’s the role of DNA
Hold genetic information in the nucleus
What is dna made up of
2 polymer chains which form a double helix
4 different monomers called nucleotides
Name the four nucleotides (CGAT)
Cytosine
Guanine
Adenine
Thymine
Ethene + water (steam) = ethanol is the equation for what
Making alcohol using ethene
