Alkenes

What is the reaction mechanism to make alkenes into haloalkanes

Electrophilic addition

Test for an alkene

Add to substance to bromine water, the solution will turn from brown to colourless

Conditions for hydrogenation

Nickel catalyst

423K

Markonnikoff rule

In electrophilic addition, the hydrogen in a hydrogen halide is more likely to join a carbon with the most hydrogen already attached

Why can electrophilic addition start

because the pi bond in an alkene is an area of high electron density so its easier to attract those electrons

What is the nature of a double bond

There is a pi bond between 2 p orbitals above and below the sigma bond between the s orbitals

can the double bond rotate

no

stereoisomerism definition

compounds with the same structural formula but different arrangement in space

what is the difference between an E isomer and Z isomer

Z isomer have their high priority groups on the zame zide and E have them on opposite sides

what are cis trans isomers

z and e isomers that have at least 1 hydrogen

what determines a high priority group when naming e/z isomers

when the next atom on the chain has a higher atom number

how can electrophilic addition occur to a non polar molecule

the negative region of a pi bond repels the shared pair of electrons, making the atom near the atom positive

What is a pi bond

The side to side overlap of p orbitals

What properties does a pi bond cause in alkenes

Not able to rotate about the double bond

Electrophiles can react with the double bond

High bond enthalpy

What are the conditions for an alkene to become an alcohol using electrophilic addition

Acid catalyst (H3PO4) and steam

What must a repeat unit have

n in bottom right, lines must come out of the square brackets

Polymerisation reaction equation for (poly)ethene

Which carbocation is most stable

Tertiary

What happens when plastic is recycled

It is cut up and reduced to pellets which can be used again for certain structures

Why can PVC not be burnt

Releases, as well as CO2, hydrogen chloride

What is an advantage of feedstock recycling

Can use unprocessed polymers

What are biodegradable polymers usually made up of

Natural materials like starch and cellulose

What are photodegradable polymers

Plants that break down in the sunlight

What is feedstock recycling

Processes that reclaim monomers, gases and oil and waste