Organic Chemistry 1 Flashcards
Alkene to Poly(alkene)
Addition polymerisation
The double bonds open up to make long chains of polymers
Alcohols to alkene
Eliminating water from alcohols
Alcohol is mixed with an acid catalyst such as Conc. H3PO4 and is then heated
Alcohol to aldehyde
Primary alcohols oxidise to aldehydes and then carboxylic acids
Potassium Dichromate (VI) Oxidising agent is used
You distil to get an aldehyde
You reflux for a carboxylic acid
Alcohol to ketone
Secondary alcohols oxidise to form ketones
You need to reflux the secondary alcohol with acidified Dichromate (VI)
Alcohol to halogenoalkane
React in nucleophillic substitution reactions to form halogenoalkanes
To make choloroalkanes:
You use PCl5 or HCl
To make bromoalkanes:
You need to react the alcohol with compounds containing the Br group. An acid catalyst is required 50% conc. H2SO4
To make iodoalkanes:
React the alcohol with PI3 made in situ by refluxing the alcohol
Halogenoalkanes to amines
Warm halogenoalkane with excess alcoholic ammonia
Nucleophillic substitution
Ammonia swaps places with halogen to form amine
Halogenoalkane to a Nitrile
Reflux halogenoalkane with Potassium Cyanide in ethanol
Nucleophillic sub
Halogenoalkane to alcohols
React with aqueous KOH
React with hydroxide ions by nucleophillic sub under reflux
Halogenoalkane to alkene
Halogenoalkane undergo elimination to form alkene
Warm alkali dissolved in ethanol is required
Needs to be heated under reflux
OH- acts a base to remove a H+ from halogenoalkane
Alkene to halogenoalkane
Alkene undergo electrophiilic addition using hydrogen halides to form halogenoalkane
Alkene to alkane
Hydrogenation
Requires nickel catalyst at 150 degrees
Alkene to alcohol
Hydration by steam at 500 degrees
Required solid Phosphoric (V) acid catalyst
Alkane to alkene
Thermal cracking
Zeolite catalyst at 95 degrees
Involves breaking the C-C bonds to form smaller hydrocarbons
Alkane to halogenoalkane
Photochemical reaction using halogens in free radical substitution reactions
Initiation- radicals are made
Propagation- radicals are used and created
Termination- radicals are destroyed
Homolytic fission
The bond breaks evenly and each bonding atoms receives one election from the bonding pair
Two electrically uncharged radicals are formed
Heterolytic fission
The blonde brakes unevenly with one of the bonded atoms receiving both electrons from the bonded pair
Two different substances can be formed—
Fractional distillation
- Crude oil is vaporised at around 350 degrees
- vaporised crude oil goes into a fractionating column and rises up through the trays. the largest hydrocarbons do not vaporise at all because their boiling points are too high. Instead they just run to the bottom to form a gooey residue
- as the crude oil vapour goes up the fractionating column it gets cooler because the Alkane molecules have different chain lengths therefore have different boiling points so each fraction condenses at different temperatures
- hydrocarbons with the lowest boiling points do not condense the drawn off as gases at the top of the column
Harmful emissions produced by fuels
•Carbon monoxide:
Toxic gas which can affect the amount of oxygen being carried around your body
•Sulfur dioxide and Oxides of Nitrogen:
Acid rain is caused by burning fuels containing sulfur.
•Oxides of nitrogen are produced when the high pressure and temperature of a car engine cause nitrogen and oxygen in the air to react together. When it escapes into the atmosphere it dissolve into the air and is converted to nitric acid which can fall as acid rain
Catalytic converters
Stay in a car exhaust and stops some pollutants from coming out
They get rid of pollutants by using a platinum catalyst to change them harmless gases
Sigma bonds
Single covalent bonds in organic molecules are sigma bonds.
It’s formed when two orbitals overlap in a straight line giving the highest possible electron density between two nuclei
High electron density between nuclei means there is a string electrostatic force of attraction between nuclei and shared pair of electrons. Meaning they have a high bond enthalpy
Pi bonds
Double bonds are made of sigma and pi bonds.
Pi bonds are formed when two loves of two orbitals overlap sideways
The electron density is spread above and below the nuclei causing the electrostatic attraction between nuclei and shared pair of electrons weaker. Making them have low bond enthalpy
Double bonds
C=C bond and the atoms attached lie in the same plane- they’re planar
Atoms can not rotate around the C=C bond due to the way the p orbitals overlap and form pi bonds
However they can rotate any single bonds in the molecule
Restricted rotation around c=c is what cause alkene stock form steroisomers
E/Z isomerism
E-isomer has the same groups positioned across the double bond
Z-isomer has the same groups either both above or both below the double bond
Atoms with higher atomic numbers are given higher priority
Cis-Trans isomerism
Cis means the same groups are in the same side of double bond
Trans means the same groups are on opposite sides of the double bond
