alkenes

Question 1

define alkenes

Answer 1

unsaturated hydrocarbons

Question 2

bonding in alkenes involves

Answer 2

a double covalent bond, a center of high electron density

Question 3

alkene –> haloalkane

Answer 3

electrophyllic addition
HBr/HCl/Br2/Cl2
room temp and shaken
the c=c bond is eelctron rich and induces a diploe in the br2 the $+ br is attracted to the c=c douible bond transferred

Question 4

alkene –> alchol 2 step process

Answer 4

electrophyllic addition
H2SO4
the c=c bond is eelctron rich and induces a diploe in the h2so4 the $+ H is attracted to the c=c douible bond
the product reacts with water to form alcohol

Question 5

the formation of major and minor products in addition reactions of unsymmetrical alkenes

Answer 5

tertiary carbocations form the most stable and primary the least stable due to postive inductive effect of the 3 alkyl groups comapred to one , the most stable is the major product and most likely to form

Question 6

addition polymers are formed from

Answer 6

alkenes where the double bond is broken to form a repeating unit

Question 7

reactivity of addition polymers

Answer 7

unreactive

Question 8

how can reaction conditions used in the production of polymer chains be altered to give plastics produced different properties

Answer 8

high pressure and high temp produces branches chain polymers with weak intermolecular forces
lower pressure and lower temp produces straight chain polymers with strong intermolecular forces

Question 9

how to name addition polymer of an alkene

Answer 9

poly(alkene)

Question 10

are polyalkenes biodegradable

Answer 10

polymers are unreactive hydrocarbon chains with multiple strong, non-polar covalent bonds, due not containing any polar bonds nucleophiles cannot attack so they are not biodegradable

Question 11

typical uses of poly(chloroethene) and why

Answer 11

plastics like shopping bags and drain pipes has waterproof properties due to addition of plasticisers during the reaction which also make is flexible enough for shopping bags and rigid enough for drain pipes

Question 12

alkene to alchol 1 step

Answer 12

direct hydration
H2O
conc H3PO4 catlyst
the c=c bond is eelctron rich and the $+ H is attracted to the c=c douible bond. lone pair on O of H2O attracted to C+

Question 13

test for alkene

Answer 13

bromine water (electrophyllic addition)
orange to colourless