Edexcel Jun 2017 (IAL) Paper 4 Q18

Answers available below

18 (a) Propanal is an isomer of propanone. It reacts with at least three reagents which do not react with propanone. (i) Identify two of these reagents, in each case stating what you would see when the reaction takes place. (4) First reagentD O N O T W R I T E I N T H I S A R E A Second reagent(ii) Each reaction is of the same type. State the type of reaction. (1)(b) Propanoic acid can be formed in the reactions in (a). (i) Give the structural formula of propanoic acid. (ii) Propyl propanoate can be made from propanoic acid in two steps. Step 1 Step 2 Propanoic acid propanoyl chloride propyl propanoate Name the reagents for each step. (1) (2) Step 1Step 216 *P48385A01628* D O N O T W R I T E I N T H I S A R E A D O N O T W R I T E I N T H I S A R E A<br /> A E R A S I H T N I E T I R W T O N O D A E R A S I H T N I E T I R W T O N O D (iii) Explain why the two step process given in b(ii) gives a higher yield than synthesising propyl propanoate from propanoic acid in one step. (1)(c) Propanal and propanone can be easily distinguished from each other by proton nmr (nuclear magnetic resonance spectroscopy) or IR (infrared) spectroscopy. *(i) Draw the displayed formula of propanal and label the different proton environments. Indicate the relative areas and splitting pattern for each peak in the high resolution proton nmr spectrum. Chemical shifts are not required. (3)A E R A S I H T N I E T I R W T O N O D(ii) State and explain the appearance of the high resolution nmr spectrum of propanone. (2)*P48385A01728* 17 Turn over<br /> (iii) Use your Data Booklet to identify two absorptions in the IR spectrum of propanal that would distinguish it from propanone. How would the IR spectrum of propanone be different from propanal? Identify the wavenumber of each absorption and the bond responsible. (3)D O N O T W R I T E I N T H I S A R E A(Total for Question 18 = 17 marks) TOTAL FOR SECTION B = 49 MARKS 18 *P48385A01828* D O N O T W R I T E I N T H I S A R E A D O N O T W R I T E I N T H I S A R E A<br /> A E R A S I H T N I E T I R W T O N O D A E R A S I H T N I E T I R W T O N O D BLANK PAGE A E R A S I H T N I E T I R W T O N O D *P48385A01928* 19 Turn over<br />

Show answer