3.5_Organic_AS91391

=3.5 AS91391 Demonstrate understanding of the properties of organic compounds (5 credits)= ==



The tables below provide an overview of the molecules and year that they appeared in the NCEA Exam paper


The structure of aspartame (artificial sweetener) is given below. Identify the FOUR different functional groups within the aspartame molecule that are circled




Click on the solution and reasons for incorrect alternative IUPAC names here


==NCEA PAST EXAM QUESTION: Draw the structural formula (aka displayed or expanded structural formula) for the following organic substances ==

The table below provides an overview of the names of the organic substance and year that they appeared in the NCEA Exam paper




__ISOMERS __

 * [[image:chiral.jpg width="213" height="133" link="@file:chiral molecule.swf"]] || [[image:lightbulb.jpg width="228" height="132" link="@file:polarimeter.swf"]] || [[image:chiral2.jpg width="423" height="130" link="@file:testing.swf"]] ||

NCEA PAST EXAM QUESTIONS on constitutional isomers and stereoisomers


(a) (i) Describe the structural feature necessary for a compound to exist as enantiomers (optical isomers).
==== (ii) Identify one physical property that is the same for both enantiomers of alanine, and one that is different, clearly describing how this property could be used to distinguish between the enantiomers. ====

(b) Draw 3-D structures of the enantiomers of alanine.


i) Draw three-dimensional structures for the two enantiomers that clearly show the relationship between them.
====ii) Alanine has two straight chain isomers that do not show acidic properties. One of these isomers, P, can exist as an enantiomer, the other isomer, Q,cannot. Draw P and Q. ====

The amino acid alanine below can exist as two enantiomers (optical isomers).


i) Draw three-dimensional structures for the two enantiomers that clearly show the relationship between them
====ii) Alanine has two straight chain isomers that do not show acidic properties. One of these isomers, P, can exist as an enantiomer, the other isomer, Q,cannot. Draw P and Q. ====

** ii) ** Explain how the two enantiomers of the compound circled above could be distinguished from each other.
==== **a** ) C5H11OH is an example of an alcohol that can exist as a number of different isomers. Draw structures of the isomers of C5H11OH that satisfy the requirements of i) a branched-chain secondary alcohol (A) and ii) a branched-chain tertiary alcohol (B) ==== ==== **b)** <span style="color: #000000; font-family: Arial,Helvetica,sans-serif;">Explain why is the only primary alcohol isomer of C5H11OH that is able to exist as a pair of enantiomers (optical isomers). ==== <span style="color: #000000; font-family: Arial,Helvetica,sans-serif;">

====a) Compound A is an isomer of C4H8O and can exist as two enantiomers (optical isomers). It contains two different functional groups – an alcohol(OH–) group and an alkene group. Draw 3-dimensional structures for both enantiomers that clearly show the relationship between them.==== ====b) Two compounds (B and C) have the same molecular formula, C4H8O. They are cis-trans isomers that contain a primary alcohol group. Both compounds rapidly decolourise bromine solution. Draw the structural formulae of compounds B and C.====

<span style="font-family: Arial,Helvetica,sans-serif;">Draw 3dimensional structures that clearly show the relationship between the two enantiomers.
<span style="display: block; font-family: Arial,Helvetica,sans-serif; text-align: left;">**ii)** Describe similarities and differences in the chemical and physical properties of the enantiomers



__<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">POLYMERS - general questions __

 * [[image:chemicalminds/l3polymermakenylon.jpg width="299" height="121" link="@file:makingnylon.swf"]] || [[image:l3knockhardypolymers.jpg width="349" height="232" link="@http://www.google.co.nz/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CB4QFjAA&url=http%3A%2F%2Fwww.knockhardy.org.uk%2Fppoints_htm_files%2Fpolypps.pps&ei=J3TVVNqQBaTYmAXdwICwCA&usg=AFQjCNG_hu2YNPvDgnHGhWQnXNYrp58Puw&sig2=AClZPS9qS5zRrDvOpnfCfA&bvm=bv.85464276,d.dGY"]] ||

<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">NCEA PAST EXAM QUESTIONS on Polymers
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">A form of the polymer nylon can be made from the two monomers below.
<span style="font-family: 'Times New Roman',serif; font-size: 16px;"> <span style="font-family: 'Times New Roman',serif; font-size: 16px;">

(iv) Elaborate on the reaction that will occur if a dilute aqueous solution of acid is mixed with the newly formed polymer.
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">• structures of the organic products formed as a result of hydrolysis.
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif; line-height: 0px; overflow: hidden;">

<span style="font-family: Arial,Helvetica,sans-serif;">• Explain why NaHCO3 is added.
<span style="font-family: Arial,Helvetica,sans-serif;">

** b) ** Compound **X** is a polymer which can be hydrolysed to give a single monomer, Compound **Y**, which has the molecular formula C 3 H 6 O 3.
Draw a section of the polymer, Compound **X**, showing at least two repeating units. ====<span style="font-family: Arial,Helvetica,sans-serif;">Lactic acid <span style="font-family: Arial,Helvetica,sans-serif;">is able to form a condensation polymer in the presence of dilute sulfuric acid. Draw three repeating units of this polymer. ====

Consider the following statement.
**//"Polyesters//** //are **polymers** that can be made from two different **monomers** or from a single monomer"// ====Discuss this statement, using the structures of specific monomers and the polyesters that can be made from them, to illustrate your answer. Your answer should demonstrate a clear understanding of the highlighted terms.====



<span style="font-family: Arial,Helvetica,sans-serif;">Glycine and alanine can combine together with the elimination of a molecule of water to produce a dipeptide – as shown below
====<span style="font-family: Arial,Helvetica,sans-serif;">Look carefully, you’ll notice that glycine and alanine can combine to form a different dipeptide because a -H can be removed from the glycine and –OH from the alanine to from a different dipeptide and a water molecule. If three amino acids are joined together eg three molecules of glycine a tripeptide is formed. ====

<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">NCEA PAST EXAM QUESTIONS on Amino Acids, dipeptides, tripeptides and proteins
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">[[image:2013sample.jpg width="236" height="39"]]
<span style="display: block; font-family: Arial,Helvetica,sans-serif; text-align: left;">**a)** Glycine and serine are two amino acids, which can combine to form dipeptides.

[[image:NCEA 2008.jpg]]
====<span style="color: #000000; font-family: Arial,Helvetica,sans-serif;">Amino acids are the building blocks that make up proteins. Alanine and valine are amino acids which can combine to form dipeptides. ====

<span style="color: #000000; font-family: Arial,Helvetica,sans-serif; line-height: 0px; overflow: hidden;">[[image:l3amino2008.jpg width="168" height="144" align="left"]]


** a) ** Draw the structure of a possible dipeptide formed from the combination of alanine and valine. ** b) ** Draw the organic products of the hydrolysis of the dipeptide below using : ** i) ** dilute hydrochloric acid solution ** ii) ** dilute sodium hydroxide solution.

<span style="font-family: Arial,Helvetica,sans-serif;">**a)** Gluthathione (GSH) is one of the most common small peptides in animals, plants and bacteria
<span style="display: block; font-family: Arial,Helvetica,sans-serif; text-align: left;">**i)** Draw a circle around one of the amide (peptide) groups. ====<span style="font-family: Arial,Helvetica,sans-serif;">**ii)** Draw structures of the products of the hydrolysis of this compound using alkaline conditions (NaOH) and compare with the structures of the hydrolysis products under acidic conditions. ==== <span style="font-family: Arial,Helvetica,sans-serif;">Compound <span style="font-family: Arial,Helvetica,sans-serif;">undergoes a condensation reaction with the following molecule  (commonly <span style="font-family: Arial,Helvetica,sans-serif;">referred to as alanine). It forms two different organic products referred to as dipeptides.

<span style="font-family: Arial,Helvetica,sans-serif;">**ii)** Explain why the formation of dipeptides is referred to as a ‘condensation reaction’.






<span style="font-family: Arial,Helvetica,sans-serif;">(i) Circle one of the alkene groups in the triglyceride molecule.
====<span style="font-family: Arial,Helvetica,sans-serif;">(ii) This triglyceride is described as unsaturated. Describe a chemical test that can be used to show that the molecule is unsaturated. Give any observations, and state the type of reaction occurring. ====

The triglyceride below is shown in condensed form.
<span style="font-family: Arial,Helvetica,sans-serif;">(i) Circle a functional group on the diagram above and give its name. ====<span style="font-family: Arial,Helvetica,sans-serif;">(ii) Compare and contrast the reaction of the above triglyceride when it undergoes both acidic and basic hydrolysis. In your answer you should include: ====

<span style="font-family: Arial,Helvetica,sans-serif;">• any reagents and conditions required for the reaction to proceed.
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">[[image:NCEA2011.jpg]]
====<span style="font-family: Arial,Helvetica,sans-serif;">Discuss the similarities and differences in the reactions of methyl propanoate, CH3CH2COOCH3, in basic conditions with NaOH, and in acidic conditions with HCl. ====

<span style="color: #000000; font-family: Arial,Helvetica,sans-serif;">**1)** Esters are often responsible for the flavouring of fruit. The compound below is an ester with a raspberry flavour.
====<span style="font-family: Arial,Helvetica,sans-serif;">Esters can be prepared by refluxing the reactants with a small amount of concentrated sulfuric acid. After refluxing, the reaction mixture is treated with potassium carbonate and distilled. ====

<span style="font-family: Arial,Helvetica,sans-serif;">• a discussion of why reflux and distillation are used in this preparation.
====**<span style="font-family: Arial,Helvetica,sans-serif;">2) ** The triglyceride shown below was heated with aqueous sodium hydroxide, NaOH. Draw the structural formulae of the two products formed in this reaction. ====

<span style="font-family: Arial,Helvetica,sans-serif;">b) Compare the products that would form if the hydrolysis occurred in basic conditions using NaOH solution
<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">

**d)** Describe a test, using a solution of bromine in a non-polar solvent, that could be carried out in the laboratory to compare the degree of unsaturation of two fats.




<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">NCEA PAST EXAM QUESTION: Distinguishing between organic compounds
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;"> ====<span style="font-family: Arial,Helvetica,sans-serif;">Identify the reagents, conditions required, and observations linked to species, to enable the following pairs of chemicals to be distinguished from each other. ====

<span style="font-family: Arial,Helvetica,sans-serif;">(iii) Propanoyl chloride and propyl propanoate.
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;"> ====<span style="font-family: Arial,Helvetica,sans-serif;">**1)** Devise a method for distinguishing between the three liquid compounds, butan-1-ol, butanoic acid, and butanoyl chloride, using only blue litmus paper and water. ====

<span style="font-family: Arial,Helvetica,sans-serif;">Explain each of the observations in your method, with reference to the structure of the organic compounds.
====<span style="font-family: Arial,Helvetica,sans-serif;">**2)** Describe how you could distinguish between methylpropan-2-ol and butan-1-ol and butan-2-ol, using chemical tests on the alcohols and / or their oxidation products ====

<span style="font-family: Arial,Helvetica,sans-serif;">Explain a laboratory procedure that would allow the following pairs of compounds to be distinguished. In your answers, you should include:

 * ====<span style="font-family: Arial,Helvetica,sans-serif;">the reagent used ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">the expected result for any reactions that may or may not occur ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">the structural formulae of the organic product(s) formed when the reaction(s) occur. ====

Explain a laboratory procedure that would allow the following pairs of compounds to be distinguished. In your answers, you should include:

 * ====the reagent used====
 * ====the expected result for any reactions that may or may not occur====
 * ====the structural formulae of the organic product(s) formed when the reaction(s) occur.====

<span style="font-family: Arial,Helvetica,sans-serif;">Describe a test that could distinguish between an amide and an amine
====<span style="font-family: Arial,Helvetica,sans-serif;">**1)** Explain how you could distinguish from propanone ====

<span style="font-family: Arial,Helvetica,sans-serif;">• the expected observations.
====**<span style="font-family: Arial,Helvetica,sans-serif;">2) **Compound X, an isomer of Compound A, C3H6O3, can exist as enantiomers. It reacts with acidified dichromate solution to give Compound Y, C3H4O3. Both compounds X and Y react with sodium carbonate to produce carbon dioxide gas. Identify Compounds X and Y and justify your answers in relation to the information above.==== ====<span style="font-family: Arial,Helvetica,sans-serif;">1) A colourless liquid is known to be a branched-chain alcohol with the molecular formula C5H11OH. Investigations of this liquid show the following ====

<span style="font-family: Arial,Helvetica,sans-serif;">Use the features listed to determine which of the alcohols A to E is the colourless liquid. Justify your answer.
====<span style="font-family: Arial,Helvetica,sans-serif;">2) Devise a method for distinguishing between propanoyl chloride, 2-amino-3-methylbutane, pentanal, 4-chlorobutanoic acid. Each test should use either moist red litmus paper or an acidified solution of potassium permanganate ==== <span style="font-family: Arial,Helvetica,sans-serif;"> ====<span style="font-family: Arial,Helvetica,sans-serif;">Discuss how to test propanal and propanoic acid to demonstrate that they are different from each other AND different from propan-1-ol. Include the observations that would allow each substance to be identified as a result of these tests. ==== <span style="color: #221e1f; font-family: 'Times New Roman','serif'; font-size: 16px;"> ====<span style="font-family: Arial,Helvetica,sans-serif;">1) The identity of a colourless liquid is unknown. It is thought to be one of the following: ethanoyl chloride (CH3COCl) or ethanol (CH3CH2OH) or 2-methyl propan-2-ol ((CH3)3COH) or hex-1-ene (CH2= CHCH2CH2CH2CH3). ====

<span style="font-family: Arial,Helvetica,sans-serif;">Describe the observations expected at each stage (equations not required).
<span style="font-family: 'Times New Roman','serif';"> ====<span style="font-family: Arial,Helvetica,sans-serif;">Describe a chemical test that would distinguish between each of the following pairs of substances. For each test, identify the reagents used, and link the observations to any reactions that may or may not occur. ==== ====<span style="font-family: Arial,Helvetica,sans-serif;">Describe chemical tests that could be used to distinguish between the compounds in each of the pairs of substances below. For each test description: ====

<span style="font-family: Arial,Helvetica,sans-serif;">Do NOT use the same test more than once.




__<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">Organic reaction pathways __

 * [[image:l3organictypereactMAP.jpg width="880" height="554" link="@file:l3organictypereactMAP.docx"]] ||
 * [[image:l3organicreaggentsMAP.jpg width="938" height="594" link="@file:l3organicreaggentsMAP.pdf"]] ||

<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">[[image:printButton.gif link="@file:l3reactpaths.docx"]]
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

Complete the following reaction scheme by drawing the structural formulae of the organic compounds **A** to **E**, and identifying reagents **1** to **5**.


<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">Include any necessary conditions, needed to bring about the transformation from reactant A to the organic compound C, which is a base.
<span style="font-family: Arial,Helvetica,sans-serif; line-height: 0px; overflow: hidden;">3) ====<span style="font-family: Arial,Helvetica,sans-serif;">When ammonia reacts with two products are formed. Complete the equation below by naming compounds or drawing the structure. ====

<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;"> ====**1)** For the following conversion, identify the reagent required and state the type of reaction occurring. You should give a reason for your answer in terms of the structure of the reactants and products.==== **<span style="font-family: Arial,Helvetica,sans-serif;">2) **<span style="font-family: Arial,Helvetica,sans-serif;"> **a)** Complete the following reaction scheme that shows some reactions starting with butanal. Give the structural formulae of the organic products A, B,and C.  ====<span style="font-family: Arial,Helvetica,sans-serif;">b) Devise and complete the reaction scheme starting with butanone in place of butanal to show how butanone would react with the reactants 1–3. In your answer, you should: ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">identify the products formed in each reaction step; state if no reaction occurs ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">write the structural formula for each product formed, including major and minor products (if any). ====

<span style="font-family: Arial,Helvetica,sans-serif;">c) Compare and contrast the two reaction schemes. In your answer, justify the reasons for

 * ====<span style="font-family: Arial,Helvetica,sans-serif;">the similarities and the differences between these two schemes ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">the products formed in each reaction. ====

<span style="font-family: Arial,Helvetica,sans-serif;">4) Use the following information to answer this question.
====<span style="font-family: Arial,Helvetica,sans-serif;">Compound W is a branched chain molecule with a molecular formula C4H10O. When Compound W is heated with excess acidified potassium dichromate it is readily oxidised to Compound X, which has acidic properties A substitution reaction occurs when Compound X is reacted with SOCl2. The molecular formula of Compound Y isC4H7OCl When Compound Y reacts with aminomethane, CH3–NH2, a substitution reaction occurs and Compound Z forms ====

<span style="font-family: Arial,Helvetica,sans-serif;">Justify your answer by explaining how you arrived at these structures from the information given above. In your answer, you should:
====<span style="font-family: Arial,Helvetica,sans-serif;">1) The haloalkane 1-chlorobutane can be used to make butanamide. One of the intermediate products is a carboxylic acid. Show, using structural formulae, how this might be achieved in a number of reaction steps. Include all reagents ==== ====<span style="font-family: Arial,Helvetica,sans-serif;">2) Alcohol A, (C4H10O) can react with Cr2O72– / H+ to give compound B which does not react with Tollens’ reagent. Compound A also reacts with SOCl2 to give a haloalkane C, which when reacted with alcoholic KOH, gives two products, D and E, which are not geometric isomers. When E reacts with H+ / H2O, A is the product. When D reacts with H+ / H2O, two products are formed, A and F. F can be oxidised to form butanoic acid. Give the structural formulae AND names for each of the compounds A to F. ==== ====Complete the following reaction scheme by naming and drawing the structural formula of each of the compounds A to F. Identify the reagents 1 to 4, including any necessary conditions, needed to bring about each transformation.====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">include other possible structural formulae you considered ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">give your reasons for rejecting the other structural formulae. ====



<span style="font-family: Arial,Helvetica,sans-serif;">[[image:NCEA2010.jpg]]
====<span style="font-family: Arial,Helvetica,sans-serif;">The haloalkane, 2-chloro-2-methylbutane, can be prepared by reacting 2-methylbutan-2-ol with concentrated HCl.i) Write an equation for this reaction using structural formulae.ii) State the type of reaction occurring, and give a reason for your answer. ==== <span style="font-family: Arial,Helvetica,sans-serif;"> ====<span style="font-family: Arial,Helvetica,sans-serif;">1) Identify the compound from these given: propanoyl chloride, 2-amino-3-methylbutane, pentanal, 4-chlorobutanoic acid that will react as described below, and draw the structural formula for each organic product formed. ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">Elimination with alcoholic KOH ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">Oxidation with Fehling’s or Benedict’s solution ====
 * ====<span style="font-family: Arial,Helvetica,sans-serif;">Substitution with aqueous KOH ====

[[image:NCEA 2008.jpg]]
<span style="color: #000000; font-family: Arial,Helvetica,sans-serif;">Complete the following reaction scheme by giving the formulae for reagents 1 to 5 and the structural formulae for the THREE organic products. ====<span style="font-family: Arial,Helvetica,sans-serif;">2-bromobutane reacts by substitution to form 2-butanol. However, if the reaction conditions are changed, an elimination reaction occurs. There are two possible products for the elimination reaction. Complete the following reaction scheme by indicating the reagents in the shaded boxes and the organic products in the other boxes for each of these reactions of 2-bromobutane. ====

**iii)** naming organic compounds X and Y, and the compound with formula CH3CH2COCl
====<span style="font-family: Arial,Helvetica,sans-serif;"> **b)** Each of the parts (i) – (iii) below refers to one step in the reaction scheme on page 2. For each part, identify the type of reaction (from the given list: addition, elimination, oxidation, polymerisation, substitution) and use the reaction in that step to explain the term. ====

<span style="font-family: Arial,Helvetica,sans-serif;">**iii)** Propan-1-ol is converted to propanoic acid.
====<span style="font-family: Arial,Helvetica,sans-serif;">**c)** When HBr is reacted with propene, there are two possible products. Discuss how the compounds formed in this reaction scheme would vary if these two products were not separated before reagent 2 is added ====

<span style="font-family: Arial,Helvetica,sans-serif;">. [[image:NCEA2004.jpg]]
====<span style="color: #000000; font-family: 'Arial','sans-serif'; font-size: 14.6667px;">The following reactions involve the loss of water. Clearly show the **structure** of one major organic product of each of these reactions. ====



__<span style="color: #f95727; font-family: Arial,Helvetica,sans-serif;">PRACTICAL PROCEDURES __

 * [[image:l3organicpracticalalcohol.jpg width="220" height="260" link="@http://www.ibchem.com/drop/swf/org/oxidation_alcohols.swf"]] || [[image:chemicalminds/l3organicaldehydes.jpg width="263" height="245" link="@http://www.ibchem.com/IB16/Section09-organic/swf/oxidation_aldehydes.swf"]] || [[image:l3reactaldehydesketones.jpg width="415" height="132" link="@http://203.200.1.30/CSIR_RootRepository/Saras/LearningObject/Packages/14/vocab/product/content/swf/chem_a2_ch05_sim_carb.swf"]]

||


 * ==<span style="color: #f95727; font-family: Arial,Helvetica,sans-serif;">Royal Society of Chemistry ==

<span style="color: #f95727; font-family: Arial,Helvetica,sans-serif;">make aspirin online!
|| == Mixed Reception, ChemCollective ==

//<span style="font-family: Arial,Helvetica,sans-serif;"> and //
====//<span style="font-family: Arial,Helvetica,sans-serif;"> familiarise yourself with skeletal formula before beginning //====

<span style="font-family: Arial,Helvetica,sans-serif;"> need clues??? email me!
||
 * [[image:RScaspirin.jpg width="468" height="352" link="@http://www.rsc.org/learn-chemistry/resources/screen-experiment/aspirin/experiment/1"]] || [[image:mixedreception.jpg width="422" height="358" link="@http://collective.chem.cmu.edu/MixedReception/game_survey/main.html"]] ||


 * [[image:ester.jpg width="480" height="405" link="@file:ester.pdf"]] || [[image:reflux.jpg width="414" height="435" link="@file:reflux.pdf"]] ||

<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">NCEA PAST EXAM QUESTION: Describe and Explain Practical Procedures in Organic Chemistry
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">Explain why the equipment below is used for hydrolysis of a triglyceride.


<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;"> ====<span style="font-family: Arial,Helvetica,sans-serif;">Instructions for the preparation of 2-chloro-2-methylpropane are given below. Read the instructions carefully and answer the questions that follow. ====

<span style="font-family: Arial,Helvetica,sans-serif;">1. Shake 10 mL of 2-methylpropan-2-ol with 30 mL of concentrated hydrochloric acid in a separating funnel for 10 minutes.
====<span style="font-family: Arial,Helvetica,sans-serif;">2. Run off the bottom acid layer and discard it. Add saturated sodium hydrogen carbonate to the organic product. Shake, releasing the tap every few seconds to relieve the pressure. ====

<span style="font-family: Arial,Helvetica,sans-serif;">3. Run off the bottom aqueous layer and discard it. Transfer into a conical flask and add some anhydrous sodium sulfate, and stir thoroughly.
====<span style="font-family: Arial,Helvetica,sans-serif;">4. Transfer the organic product into a round-bottom flask, and collect the fraction boiling within 2oC of the boiling point of 2-chloro-2-methylpropane. ====

<span style="font-family: Arial,Helvetica,sans-serif;">(ii) Explain why anhydrous sodium sulfate is added in instruction 3.
====<span style="font-family: Arial,Helvetica,sans-serif;">(iii) Name the process used in instruction 4 to purify the organic product. Write the number of the equipment that a student would use to perform this process from the diagrams below. ====

<span style="font-family: Arial,Helvetica,sans-serif;">• identify the reagents used, and explain any observations made.
<span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">

** i) ** Refluxing is often required in reactions involving organic substances. Circle the letter of the apparatus below that would be used in this procedure.
<span style="display: block; font-family: Arial,Helvetica,sans-serif; text-align: left;">**ii)** Discuss why refluxing is sometimes used. <span style="font-family: Arial,Helvetica,sans-serif; line-height: 0px; overflow: hidden;">

====<span style="color: #000000; font-family: Arial,Helvetica,sans-serif;">A description of a laboratory procedure that could be used for the preparation of 2-chloro-2-methylbutane from 2-methylbutan-2-ol, is given in the table below. ==== <span style="display: block; font-family: Arial,Helvetica,sans-serif; text-align: left;">Discuss this procedure by:

<span style="font-family: Arial,Helvetica,sans-serif;">- distillation apparatus
<span style="font-family: Arial,Helvetica,sans-serif;">

<span style="font-family: Arial,Helvetica,sans-serif;">**ii)** Draw and name the structure of the organic product.
====<span style="font-family: Arial,Helvetica,sans-serif;">**b)** In the preparation, the impure organic product was initially separated from the reaction mixture. Aqueous sodium carbonate was added to the organic product and when reaction ceased, the organic product was again separated. Anhydrous magnesium sulfate was added to the organic product, which was then transferred to a flask and purified by distillation. ====

<span style="font-family: Arial,Helvetica,sans-serif;">Using one or more of the sets of apparatus shown, discuss how each of the separation processes, identified in italics above, is carried out.
<span style="font-family: Arial,Helvetica,sans-serif;"> <span style="display: block; font-family: Arial,Helvetica,sans-serif; text-align: left;">The sequence below summarises, in part, the reactions for the preparation of an organic compound, F. <span style="display: block; font-family: Arial,Helvetica,sans-serif; text-align: left;">**a)** Draw and name the structure of an ester molecule that is a structural isomer of compound C above.

<span style="font-family: Arial,Helvetica,sans-serif;">**i)** Draw the structural formula of compound B and name it.
====<span style="font-family: Arial,Helvetica,sans-serif;">**ii)** Describe how the conditions in part (b) could be modiﬁed to produce compound B rather than compound C as the major product. Give reasons for these modiﬁcations. ====

<span style="font-family: Arial,Helvetica,sans-serif;">**ii)** Identify reagent G.
====<span style="font-family: Arial,Helvetica,sans-serif;">**f)** Compound E can be hydrolysed by reaction with aqueous sodium hydroxide. Name the products of this hydrolysis reaction and draw the structural formula for each. ==== <span style="color: #f95725; font-family: Arial,Helvetica,sans-serif;">



<span style="display: block; height: 1px; left: -40px; overflow: hidden; position: absolute; top: 20827px; width: 1px;"> i) Draw the monomer(s) from which this polymer is formed. ii) Discuss the hydrolysis of the polymer.In your answer you should include: • the conditions under which it can be hydrolysed • structures of the organic products formed as a result of hydrolysis.