Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

chemistry > year 1 organic chem > Flashcards

year 1 organic chem Flashcards

1
Q

what are isomers

A

molecules that have the same molecular formula but their atoms are arranged differently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are structural isomers

A

molecules that have the same molecular formula but a different structural formula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the different types of structural isomer

A

-chain (different carbon chain)
-position (functional group in different position)
-functional group (different functional group)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are stereoisomers

A

-same molecular and structural formula but a different arrangement of atoms in space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how do stereoisomers arise

A

restricted rotation around C=C double bond
each carbon in double bonds has 2 different groups attached

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

give every step of FRS of C2H6 to make C2H5Cl

A

intitiation: Cl2 –> 2Cl*
propagation 1: C2H6 + Cl* –> C2H5* + HCl
propagation 2: C2H5* + Cl2 –> C2H5Cl + Cl*
termination: C2H5* + Cl* –> C2H5Cl
overall: C2H6 + Cl2 –> C2H5Cl + HCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how is ozone formed

A

O2 –> 2O (by UV radiation)
O + O2 –> O3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how is ozone depleted

A

O3 –> O2 + O (by UV radiation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are CFCs

A

non-flammable, unreactive compounds that contain carbon, fluorine and chlorine
diffuse into stratosphere where UV light proves energy to break C-Cl bond, forming Cl* radicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the propagation reactions in the depletion of ozone and what is the role of Cl*

A

O3 + Cl* –> O2 + ClO
O3 + ClO –> 2O2 + Cl
overall: 2O3 –> 3O2
Cl has acted as a catalyst as it is regenerated and doesn’t appear in the overall equation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is a nucleophile

A

an electron pair donor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

why do nucleophilic substitution reactions happen to haloalkanes

A

-difference in electronegativity between C-X(halogen)
-C is slightly positive
-electron pair on nuclephile attracted to C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the reactants and conditions in nucleophilic substitution

A

alcohol- KOH, aqueous
nitrile- KCN, aqueous alcoholic
amine- NH3, XS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

evaluate fermentation as a method to produce alcohols

A

C6H12O6 –> 2C2H5OH + 2CO2 (exothermic)
glucose from sugar cane is fermented with yeast under anaerobic conditions, producing ethanol and CO2
optimum temp for enzymes in yeast 50-60 degrees
adv: cheap equipment, renewable resources
disadv: batch process-slow, ethanol needs to be purified by fractional distillation- time and money

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

evaluate hydration of alkenes as a method to produce alcohols

A

C2H4 + H2O –> C2H5OH
steam and H3PO4 catalyst
adv- continuous process- fast
-no waste products - 100% atom economy
disadv- non-renewable resource
-high temp, lots of energy used - expensive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is a biofuel

A

a fuel made from biological material that has recently died

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

advantages and disadvantages of biofuel

A

adv- made from renewable resources- more sustainable
usually classed as carbon neutral
disadv- petrol engines would have to be modified to store fuel with such a high ethanol conc
growing crops for biofuel takes up large areas of land

18
Q

equations that suggest biofuel is carbon neutral

A

photosynthesis:
6CO2 + 6H2O –> C6H12O6 + 6O2
production of ethanol:
C6H12O6 –> 2C2H5OH + 2CO2
combustion of ethanol:
2C2H5OH + 6O2 –> 4CO2 + 6H2O

19
Q

why might biofuel not be carbon neutral

A

fossil fuels need to be burnt for machinery to harvest the crops, refine and transport the bioethanol which produces CO2.

20
Q

what is an electrophile

A

an electron pair acceptor

21
Q

what is the major product in electrophilic addition

A

tertiary carbocations- more alkyl groups which are electron pushing- more stable

22
Q

what are addition polymers

A

-made from alkenes
-double bond opens up and monomers join together to form on long saturated chain
-exothermic reaction

23
Q

properties of addition polymers

A

-non polar, insoluble in water and generally unreactive (non-biodegradable)
-used as insulation/packaging
-only VDW
-longer chains = stronger VDW
-plasticisers make polymers more flexible

24
Q

how to maximise yield of product in distillation

A

-cool receiving flask
-don’t let temp get high than b.p of product

25
Q

precautions when refluxing

A

-don’t seal end of container as build up of gas increases pressure and apparatus may explode
-anti-bumping granules make small bubbles form rather than large

26
Q

oxidation of alchols

A

primary–> aldehydes (distillation, acidified K2Cr2O7)
primary–> carboxylic acid (reflux, XS acidified K2Cr2O7)
secondary–> ketones (reflux, acidified K2Cr2O7)

27
Q

conditions for elimination of alcohols

A

conc H2SO4 catalyst
reflux

28
Q

conditions for elimination of haloalkanes

A

KOH, ethanolic

29
Q

test for alkenes

A

orange bromine water turns colorless

30
Q

test for carboxylic acids

A

add sodium hydrogen carbonate
CO2 effervescence produced that can be tested by limewater

31
Q

test for alcohols

A

primary and secondary alcohols turn orange acidified potassium dichromate green

32
Q

test for aldehydes

A

tollen’s reagent forms silver mirror

33
Q

test for haloalkanes

A

nitric acid
sliver nitrate

34
Q

what is the molecular ion peak in mass spec

A

clear peak with largest m/z ratio (furthest right)
indicates molecular mass of molecule

35
Q

describe fractional distillation of crude oil

A

-crude oil is vaporised
-fed into fractionating column
-largest hydrocarbons don’t vaporise. they form residue at the bottom
-fractionating column is cooler at the top
-different chain lengths have different boiling points and condense at different temperatures at different levels of the column
-hydrocarbons with the lowest boiling points don’t condense and are drawn off as gases from the top

36
Q

what is each fraction used for

A

-LPG gas - camping gas
-petrol
-kerosene - jet fuel, central heating fuel
-gas oil - diesel fuel
-fuel oil - ships, power stations
-bitumen - road surfacing

37
Q

describe thermal cracking

A

-high temp and high pressure
-produces a lot of alkenes
-alkenes used to make polymer

38
Q

describe catalytic cracking

A

-zeolite catalyst
-slight pressure and high temperature
-mainly produces aromatic hydrocarbons

39
Q

why is carbon monoxide bad

A

poisonous as it binds to haemoglobin rather than oxygen
can be removed from exhaust gases by catalytic converters

40
Q

why is carbon bad

A

-soot causes respiratory problems
-can build up in engines causing them not to work properly

41
Q

why are oxides of nitrogen bad

A

causes respiratory problemss

42
Q

why is SO2 bad

A

causes acid rain, killing vegetation, fish and corroding buildings

chemistry (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions