F334 Flashcards
What is a carbonyl group?
C=O
What is the functional group of a ketone?
R-C(=O)-R’
What is the functional group of an aldehyde?
R-C(=O)-H
How are aldehydes named?
-al
How are ketones named?
-one
What are the reagents and conditions for the formation of aldehydes and ketones by oxidation of alcohols?
Acidified potassium dichromate(VI)
Reflux for ketone
Distillation for aldehyde
What is the colour change in oxidation of alcohols?
Orange to green
What are the reagents and conditions for the oxidation of aldehydes?
Fehlings solution
OR
Hear under reflux
Acidified potassium dichromate(VI)
What is the colour change for oxidation of aldehydes using Fehlings solution?
Blue to orange brown solid when heated
What are the reagents and conditions for the reduction of aldehydes and ketones?
NaBH4
What is formed when HCN is reacted with an aldehyde or ketone in an addition reaction?
2-hydroxynitrile
What is the mechanism for the reaction between an aldehyde or ketone and HCN?
Nucleophilic addition
What can be used to detect C=C bonds?
Bromine solutions
What is formed when phenol or carboxylic acid react with a strong base?
A salt
What is produced when carboxylic acid reacts with a carbonate?
Carbon dioxide and water
What colour is formed when phenol is reacted with iron(III) chloride?
Purple
What are the reagents and conditions for the formation of esters from alcohol and carboxylic acid?
Concentrated hydrochloric acid
Heated
What is reacted with phenol to form an ester?
Acyl chloride or acid anhydride
What are the reagents and conditions for the dehydration of alcohol?
Vapour passed over hot alumina
300C
How is salicin converted into salicylic acid?
Hydrolysis and oxidation by the body
How does ionisation occur in a mass spectrometer?
Stream of electrons fired
What are the sections in a mass spectrometer?
Ionisation area
Acceleration area
Drift region
Ion-detector
How does acceleration occur in a mass spectrometer?
Negatively charged plates
What are the key features of a rearrangement reaction?
Same number of products as reactants
100% atom economy
What is the atom economy of an addition reaction?
100%
What is the order of highest to lowest atom economy for different reaction types?
Rearrangement and addition
Substitution
Elimination
How are polyesters made?
Reacting a diol with a dicarboxylic acid
What are the reagents and conditions for the formation of an ester from a phenol?
Acid anhydride - heated under reflux, absence of water
Acyl chloride - room temperature, absence of water
What are the reagents and conditions for ester hydrolysis?
Dilute sulphuric acid
OR
Add an alkali
What is the technique for TLC?
Spot on pencil line 1cm from base of plate
Suspend in beaker with solvent below line and cover beaker
Remove plate when solvent front near top
Mark where front is and allow to dry
Locate spots with ninhydrin
What are acids?
Proton donators
What are bases?
Proton acceptors
What is an oxonium ion?
(H3O)+
What is amphoteric?
Substance which can behave as both acid and base
What are the properties of amines caused by its
Lone pair?
Soluble in water
Base
Ligand
Nucleophile
How are amides formed?
Amine reacted with acyl chloride
What are the reagents and conditions for the hydrolysis of amides?
Heated under reflux
Acid or alkali catalyst used
What is formed in acid amide hydrolysis?
Carboxylic acid and (NH4)+
What is formed in alkali amide hydrolysis?
Carboxylate ion and amine
What are nylons?
Polyamides
What are uses for degradable polymers?
Stitches
Medicine delivery
What are liquid crystals?
Materials with a physical state between liquid and solid
When melted it still keeps some particle orientation
How are polymers recycled?
Process scrap recycling - left over from production Post-use plastic recycling Feedstock recycling Use of bioplastics Recycling other materials
What are biopolymers?
Made by living organisms and broken down by bacteria
What are synthetic biodegradable plastics?
Broken down by bacteria
What are photodegradable plastics?
Broken down by sunlight
How do biopolymers get broken down?
Broken down by bacteria when little glucose
How are synthetic biodegradable plastics broken down?
Contain starch granules which get broken down by bacteria
Breaks into small pieces
What are aramids?
Aromatic amides
What is kevlar?
Aramid
Straight chains
Solvent of concentrated sulphuric acid
What are the properties of kevlar?
Strong
Fire-resistant
Flexible
What is Tg?
Temperature below which polymers are brittle
What is Tm?
Temperature above which polymer becomes a viscous fluid
How can Tg values be lowered?
Copolymerisation
Plasticisers
Why does a polymers tensile strength increase with chain length?
More tangled - slide over each other less
More points of contact
What is crystalline?
Areas in a polymer where the chains are closely packed in a regular way
How can crystallinity of a polymer be increased?
Cold-drawing
What are fibrous proteins used for?
Structural materials
What are globular proteins used for?
Maintenance and regulation of processes
What are zwitterions?
Particles containing both negatively charged and positively charged groups
What is the bond between two amino acids?
Peptide link
What is the reaction which bonds two amino acids?
Condensation reaction
What is a proteins primary structure?
The order of amino acids
What is a proteins secondary structure?
The a-helix or B-sheet
What is a proteins tertiary structure?
Its overall shape
What are the reagents and conditions for the hydrolysis of peptides and proteins?
Boiling
Moderately concentrated HCl
What is non-superimposable?
Two mirror image isomers
What is a chiral centre?
Carbon atom bonded to four different groups
What is another name for optical isomers?
Enantiomers
How can you tell if something is a L-enantiomer?
Obeys the CORN rule
COOH, R, NH2 looking down from hydrogen. Goes clockwise
What shape and angle does methane have?
Tetrahedral
109 degrees
What shape and angle does water and ammonia have?
Bent and pyramidal respectively
109 degrees
What bond angle do linear molecules have?
180 degrees
What shape and angle do molecules with 3 groups of electrons have?
Planar triangular
120 degrees
What shape and angle do molecules with 5 groups of electrons have?
Trigonal bipyramidal
120 or 90 degrees
What shape do molecules with 6 groups of electrons have?
Octahedral
What does an E isomer have?
Double bond with groups opposite each other
What are the four important bonds in protein chain folding?
ID-ID
Hydrogen bonds
Ionic
Covalent
What properties do enzymes have?
Catalysts
Highly specific
Sensitive to pH
Sensitive to temperature
What is the model of enzyme catalysis?
Enzyme + substrate->enzyme-substrate complex->enzyme-product complex->enzyme+products
What are enzyme inhibitors?
Molecules that bind to an active site but cannot be catalysed
What is rate of reaction?
The rate at which reactants are converted into products
What are methods of measuring rate of reaction?
Volume of gases produced Mass changes pH measurements Colorimetry Chemical analysis and titration
How can you work out order of a reaction with respect to a reactant?
Plot initial rate against concentration
What does the rate equation give us information about?
Rate-determining step
How can you tell the number of moles of substances in the rate-determining step?
It’s the same as the order of reaction of those reactants
What are the major uses of enzymes in food production?
Producing glucose syrup
Making cheese
What effect do enzymes have on atom economy?
Increases it
What is the technique for colorimetry?
Filter with complementary colour Range of standard solutions Zero using pure solvent Measure absorbances of standards Plot calibration curve Measure unknown absorbance and use curve
What is stage 1 of the steelmaking process?
Scrap steel and 300 tonnes of molten iron added
Mg added via lance to remove MgS
What is stage 2 of the steelmaking process?
Oxygen blow
Removes CO, MnO and FeO
What is stage 3 of the steelmaking process?
Calcium oxide and magnesium oxide added
React with phosphorous oxide and silicon dioxide
Calcium and magnesium phosphates and silicates removed
What is stage 4 of the steelmaking process?
Aluminium added
Aluminium oxide removed
What is stage 5 of the steelmaking process?
Substances added to meet specification
What is the process of rusting?
Oxygen reduced to hydroxide ions
Iron oxidised to Fe2+
Those ions form Fe(OH)2
Which reacts with oxygen to form Fe2O3.xH2O (rust)
What are methods of preventing rust?
Paint
Sacrificial metal
What is a coordination number?
The number of bonds from the central ion to ligands