Identify the functional groups which are present in only one structure of glucose.

Sucrose is a disaccharide formed from \(\alpha \)-glucose and β-fructose.

Deduce the structural formula of sucrose.

Starch is a constituent of many plastics. Suggest one reason for including starch in plastics.

Suggest one of the challenges scientists face when scaling up the synthesis of a new compound.

Only in straight chain form:
carbonyl
OR
aldehyde

Only in ring structure:
hemiacetal

Accept functional group abbreviations (eg, CHO etc.). 

Accept “ether”.

[2 marks]

correct link between the two monosaccharides

Correct 1,4 beta link AND all bonds on the 2 carbons in the link required for mark.

Ignore any errors in the rest of the structure.

Penalize extra atoms on carbons in link.

[1 mark]

plastic «more» biodegradable/degrades into nontoxic products
OR
plastic can be produced using green technology/renewable resource
OR
reduces fossil fuel use/petrochemicals
OR
easily plasticized
OR
used to form thermoplasts

[1 mark]

minimize «negative» impact on environment
OR
minimize waste produced
OR
consider atom economy
OR
efficiency of synthetic process
OR
problems of side reactions/lower yields
OR
control temperature «inside large reactors»
OR
availability of starting/raw materials
OR
minimize energy costs
OR
value for money/cost effectiveness/cost of production

[1 mark]