Compounds W, X, Y and Z are isomers of each other with the molecular formula C｡H,CIO. All four isomers contain a benzene ring. Only one of the isomers contains a chiral centre. The results of six tests carried out on W, X, Y and Z are shown in the table. observations with each isomer test W X Y Z 1 add cold AgNO3(aq) white ppt. forms immediately none white ppt. forms very slowly none 2 heat with NaOH(aq), white ppt. none white ppt. none then add dilute HNO3 + AgNO3(aq) 3 add NaOH(aq) + I2(aq) none pale yellow ppt. none none 4 warm with Fehling's none none red ppt. none solution 5 add cold, dilute, no change no change no change decolourises acidified KMnO4(aq) 6 add Br2(aq) no change no change no change decolourises and forms white ppt.

1. (a)Use the experimental results in the table above to determine the group(s), in addition to the benzene ring, present in the four isomers W, X, Y and Z. Complete the table below, identifying the group(s) present in each isomer. group(s) in compound W X Y Z[5]
2. (b)(i)Use the information in (a) to suggest a structure for each of these isomers and draw these in the boxes. W X Y Z[4]
3. (b)(ii)Draw a circle around the chiral centre in one of the above structures.[1]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.