organic chemistry

Question 1

what is tructural isomerism

Answer 1

same molecular formula but different structural formula

Question 2

what is serioisomerism

Answer 2

is the same structural formula but atoms and bonds arranged differtly in space

Question 3

why does alkenes produce ez sterioisomerism

Answer 3

due to restriction rotaion on the douvble bond

Question 4

what is the feature of the homologous chromosomes

Answer 4

it differs by a functional and specific group
as the chain length increases more electrons so more vanderwall forces between molecules so greater boiling points and melting point
as brnching increases it decreases the boiling points as it cant pack very closely together
chemical reaction is the similair

Question 5

what is polarity and solubility and reactions fr alkanes

Answer 5

bonds non polar as similair electronegativity this means only vdw forces between molecules much weajker than dipole or hydrogne bonding insoluble as doesnt have enough strength to interact between hydrogen bonding can react and release energy in combustion

Question 6

how does fractional distillation work

Answer 6

the crude oil is heated in a blast furnace and then the gasses are passed through a colum it is coolest at the top and warmest at the bottom the vapours condense and whhen reaches a cool it cools and condenses and forms liquid and pipes off forming different fraction at the bottom is bitument which is like tar

Question 7

why is cracking needed

Answer 7

there is small need for the fuel oil na d longer hydrocarbon and ore need for smaller hydrocarbons

Question 8

what is thermal cracking

Answer 8

high temperatures and high pressure of 720-1200 and 7200 kpa this then is cracked here the carbon carbon bond is broken homolytically leaving free radicals these then can react however not enough hydrogen bonds so form alkenes thermal cracking leads large amoun of alkens being formed only left for a short period of time as highly reactive also form hydrogen

Question 9

what is catalytic cracking

Answer 9

it is medium temp and pressure 720 k and low pressure using a zeolite catalyst which is acidic honeycome structure it cracks and forms more branched molecules and chains aromatic compound and cycloalkanes
products may be futher cracked

Question 10

what happens in incoplete combustion

Answer 10

can either form incompkete combustion carbon monoxide or can form soot

Question 11

how is the atmosphere polluted

Answer 11

using carbon monoxide it is a poisonous gas
nitrogen ad oxygen from the air react at high temperature in the exhaust forming nitrogen oxides whcih can also react with water vapour and form aciidc rain
the sulphur impurities react with oxygen and water to form sulfur dioxid and acid rain
c02 is released and unburt hydrocarbons

Question 12

how does nitrogen dioxide and carbon monoxide form into

and what does hydrocarbon and nitrogen form

Answer 12

nitrogen and carbon dioxide

h20 and nitrogen and c02

Question 13

what is a nucleophile

Answer 13

electron donor

Question 14

give all the nucleophillic substitutions reaction

Answer 14

oh aqueasu and it is ehtanoic
cynaide ehtano
concentrated sulfuric acid and ethanol

Question 15

how does oh act as a base with alkanes

Answer 15

in elimination reaction forming an alkene ethanol and hot

Question 16

how is a carbon cation formed

Answer 16

the alkyl group ghave electron releasing effect which make the carbon more stable the greater the positive inducity effect the greater the stability

Question 17

what are plasticiers

Answer 17

added in between polyere seperate and space out the chain so less packed together so make nmore flexible do better related to its function

Question 18

why are addition polymers not biodegradble

Answer 18

large amount of carbon and hydrogen very highly unreactive so cannot be broken down

Question 19

how are different plastics made

Answer 19

low density is made high pressure and high temperature and a zeolite catayst it creates free radical reaction and lead to a lot of branhcing so doesnt pack very closlely so weak and flexibe used for carrier bags
hgih density is made from medium and low temperature with a niegller catalyst it forms unbranched chains fairy stright and rigid can be used for drain

Question 20

how to recycle plastic

Answer 20

wash the plastic and then pack into pellets these can then be melted and form and mould into different types of plastic

Question 21

what is the genral formula of alchohol and the ohysical properties

Answer 21

cnh2n+1oh is small carbon chain molecules there are hydrogen bonding which is as well as vdw forces so greater bp

Question 22

how is ethanol industrially made

Answer 22

using phosphoric acid steam and high pressure

Question 23

how is ethanol dehydrated

Answer 23

using hot concentrated sulphuric acid or phosphoric acid

Question 24

how is ethanol changed to ethanal

Answer 24

simple distillation

Question 25

how is ethanal changed into ethanoic acid

Answer 25

using concentratted acid and potassium dichromate and a refluxingthe ehtanol boils evaporates and then condesnses so it can fully oxidise

Question 26

What happens in Tolkien’s reagent

Answer 26

The ag + ions are reduced to silver atoms and then deposit on the surface have no effects on a ketone

Question 27

Why is alcohol a good fuels

Answer 27

It doesn’t contain sulcus impurities and it also can be made using renewable materials

Question 28

How does infrared spec work

Answer 28

All bonds have specific frequency which the vibrate theses can be detecting passing the radiation through the compound and the absorbable

Question 29

What is the fingerprint religion

Answer 29

All compunds have a fingerprint region which allow to detect a compound as all bonds vibrate with specific vibration 
Oh bond is broad
Oh bond is very broad
Co is sharp
Can be used to detect water and co2