Edexcel Chemistry Unit 5 Reactions

Does anyone know exactly what organic reactions I need to know for edexcel unit 5 chemistry? I read the specifications but i dont really understand what I exactly need. Its seems very generic to me. Does anyone have a detailed list of reactions to learn? Thanks in advance!!

Reply 1

sphixter

Guys?

Reply 2

sphixter

Noone here does Edexcel Chemistry?

Reply 3

charco

Study Forum Helper

Ten seconds search on Google....

Topic 5.3: Organic chemistry III (reaction mechanisms and aromatic
compounds)
Questions set on this topic may require the application of knowledge covered in topic 2.2 and topic 4.5; specifically the rules for nomenclature and the ideas of isomerism, bond polarity and bond enthalpy, including reagents and the reaction conditions in these topics.
The application of reaction mechanisms to organic chemical changes is considered a synoptic skill within this unit and Unit 6B.
The inclusion of a compound in this topic does not imply that practical work should be carried out with the compound. Benzene must not be used in laboratories at this level.
a Structure of benzene and reactions of aromatic compounds
Students should be able to use the concepts of the different types of covalent bonds, and bond enthalpy to explain the structure and stability of the benzene ring
• students may represent the structure of benzene as or in equations and mechanisms
• benzene is chosen as the exemplar for electrophilic substitution in aromatic systems to remove the need for students to become involved in discussion about the orientation of substitution
Students should be able to recall, in terms of reagents and general reaction conditions, the reaction of:
i benzene with a nitrating mixture; bromine and chloroalkanes and acid chlorides in the presence of anhydrous aluminium chloride
ii aromatic compounds with carbon-containing side chains with alkaline potassium manganate(VII) solution, resulting in the oxidation of the side-chains
iii phenol with sodium hydroxide, bromine and ethanoyl chloride
iv aromatic nitro-compounds with tin and concentrated hydrochloric acid reducing them to amines
v phenylamine with nitrous acid; and the subsequent coupling reaction of benzenediazonium ions with phenol.
b Reaction mechanisms
The convention of to represent movement of an electron pair will be expected. Students should be able to recall the following reaction mechanisms together with reagents and general conditions for the reactions shown and apply them to simple allied reactions.
• reaction mechanism: students should be able to illustrate each of the reaction types with specific examples and be able to write an overall equation for the reaction chosen
i homolytic, free radical substitution (alkanes with chlorine)
• students should understand that the reaction of a molecule with a free radical will generate another free radical and that reaction between free radicals provides a termination reaction
• students should be encouraged to use the convention to represent the movement of a single electron from a pair of electrons in radical reactions
• students are not expected to carry out these reactions in the laboratory
ii homolytic, free radical addition (polymerisation of ethene)
iii heterolytic, electrophilic addition (symmetrical and unsymmetrical alkenes with halogens and hydrogen halides)
• a statement of Markovnikov’s Rule will not be examined
• explanations of the orientation of addition should be in the context of the relative stability of the intermediate carbocation.
iv heterolytic, electrophilic substitution (benzene with a nitrating mixture, with bromine and with chloroalkanes and acid chlorides)
• the generation of the electrophile, eg NO2+ must be shown as part of the mechanism
• the orientation of substitution in benzene derivatives will not be examined
v heterolytic, nucleophilic substitution (halogenoalkanes with hydroxide ions and cyanide ions) SN1 and SN2.
• students are not expected to carry out reactions involving cyanide
vi heterolytic, nucleophilic addition (carbonyl compounds with hydrogen cyanide).

Topic 5.4: Chemical kinetics II
Knowledge of the concepts introduced in Unit 2 will be assumed and extended in this section
Students should be able to:
a recall that rates of reaction may be expressed by empirical rate equations of the form:
rate = k[A]mn, where m and n are 0, 1 or 2
b define the terms rate constant and order of reaction and understand that these are experimentally determined
• the concept of molecularity is not required
c deduce rate equations from given experimental initial rate data
d recall that reactions with a large activation energy will have a small rate constant
• students will be expected to be familiar with the Arrhenius equation but not to recall it
e understand that many reactions take place in several steps, one of which will be the rate-determining step
f understand that it is sometimes possible to deduce information regarding the mechanism of a chemical reaction from kinetic data
g understand that many reactions proceed through a transition state
h select and describe a suitable experimental technique for following a given reaction
i present and interpret the results of kinetic measurements in graphical form
j define the term half-life and recall that this is constant for any given first-order reaction.
• questions requiring a knowledge of the products of the radioactive decay will not be asked

Topic 5.5: Organic chemistry IV (analysis, synthesis and application)
Questions set on this topic may require the application of knowledge covered in topics 2.2, 4.5 and 5.3.
This topic is considered to contain material of a synoptic nature.
a Organic analysis
Students should be able to:
i describe practical tests or combinations of tests to confirm the presence of the following functional groups:

• students will be expected to describe tests to distinguish between primary, secondary and tertiary alcohols
• the halide group may be identified by simple alkaline hydrolysis, subsequent acidification and testing with aqueous silver nitrate
• other groups may be identified by reactions of the student’s choice, but the reactions of the common reagents bromine solution, phosphorus pentachloride, 2,4-dinitrophenylhydrazine solution, Fehling’s solution and ammoniacal silver nitrate, sodium or potassium hydrogencarbonate, iodine in the presence of alkali (or potassium iodide and sodium chlorate(I)) solution, will be expected to be known
ii interpret physical data and chemical information, including information relating to derivatives where appropriate, to arrive at the structural formula of a compound
iii a interpret simple fragmentation patterns from a mass spectrometer
b interpret simple infra-red spectra
c interpret simple low-resolution nuclear magnetic resonance spectra
• limited to proton magnetic resonance
d interpret simple ultra-violet/visible spectra.
• students will not be expected to describe the theory of or the apparatus connected with the production of uv – visible, infra-red or nuclear magnetic resonance spectra
• students will be given tables of data as appropriate.
• students will not be expected to recall specific spectral patterns and/or wave numbers, but may be required to inspect given spectra and tables of data to draw conclusions
b Organic synthesis
Students should be able to:
i propose practicable pathways for the synthesis of organic molecules
ii propose suitable apparatus, conditions and safety precautions for carrying out organic syntheses, given suitable information
iii demonstrate familiarity with a range of practical techniques used in organic chemistry
• mixing, heating under reflux, fractional distillation, filtration under reduced pressure (filter pump and Buchner funnel), recrystallisation, determination of melting temperature and boiling temperature, and heating with a variety of sources, whilst having a regard for safety, typify some of these practical techniques. When considering aspects of laboratory safety students will be expected to relate these to the specific hazards of the reaction or chemicals being handled.
• it will be assumed that students wear eye protection during all practical work
iv demonstrate an understanding of the principles of fractional distillation in terms of the graphs of boiling point against composition.
• students will not be expected to recall experimental procedures for obtaining graphs of boiling point against composition
• knowledge of systems that form azeotropes will not be expected
c Applied organic chemistry
Students should be able to appreciate the importance of organic compounds in pharmaceuticals, agricultural products and materials. Questions will be confined to the following aspects:
i changes to the relative lipid/water solubility of pharmaceuticals by the introduction of non-polar side-chains or ionic groups
ii the use of organic compounds such as urea as sources of nitrogen in agriculture and their advantages as compared with inorganic compounds containing nitrogen
iii the use of esters, oils and fats
• to include flavourings, margarine, soaps and essential oils
• oils and fats to be considered from the viewpoint of saturation
iv properties and uses of addition polymers of ethene, propene, chloroethene, tetrafluoroethene and phenylethene, and of the condensation polymers (polyesters and polyamides).
• this should include consideration of the difficulties concerned with the disposal of polymers
• no specific reactions will be the subject of recall questions. Students will be expected to give some examples of compounds and reactions to illustrate their answers.

How long have you been waiting?

Reply 4

sphixter

That's the sylabus word for word. The thing is I don't really understand what exact reactions I need. Take for example, benzene with a nitrating mixture - What nixtrating mixture? So I wanted a list of the exact reactions I needed like there was in AS. Thanks for answering anyway.

Reply 5

zahra_89

Theres a really good summary in the 'Making the Grade' revision guide if you have that. There aren't as many reactions for unit 5 than for unit 4.

Reply 6

zahra_89

Or have a look at chemguide.co.uk
that is pretty much geered towards the edexcel syllabus.

Reply 7

RMIM

From my make the grade chemistry book (just give u an outline)

Summary of aromatic substances
A. Benzene plus
1. conc HNO3 and H2SO4
2. Br2
3.C2H5Cl (halogenoalkane)
4. CH3COCl (acid chloride)/cat. AlCl3

B. Phenol plus 1. OH- 2. Br2 3. Acid chloride

C. Phenyamine plus 1. H+ 2. HNO2

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Some work on mechanisms.
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And revise all the organic work in unit 2 and 4!