Polymers and Organic Chemistry structured questions · GCE A-Level H1 Chemistry

Learning objectives

• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — hydrocarbons (alkanes, alkenes and benzene)
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — halogenoalkanes
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — alcohols (including primary, secondary and tertiary)
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — aldehydes and ketones
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — carboxylic acids
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — esters
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — amines
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — amides
• interpret, and use the nomenclature, general formulae and structural formulae (including displayed formulae) of the following classes of compounds: — amino acids
• interpret, and use the following terminology associated with organic reactions: — functional group
• interpret, and use the following terminology associated with organic reactions: — addition, substitution, elimination
• interpret, and use the following terminology associated with organic reactions: — condensation, hydrolysis
• interpret, and use the following terminology associated with organic reactions: — oxidation and reduction [in equations for organic redox reactions, the symbols [O] and [H] are acceptable]
• describe constitutional (structural) isomerism
• describe cis-trans isomerism in alkenes, and explain its origin in terms of restricted rotation due to the presence of π bonds [use of E, Z nomenclature is not required]
• deduce the possible isomers for an organic molecule of known molecular formula
• — describe the shapes of the ethane, ethene and benzene molecules
• — explain the shapes of, and bond angles, in the ethane, ethene and benzene molecules in relation to σ and π carbon-carbon bonds [knowledge of hybridisation is not required]
• — predict the shapes of, and bond angles in, molecules analogous to those specified in (f)(ii)
• describe the chemistry of the following classes of compounds: — alkanes (exemplified by ethane) as being generally unreactive except in terms of combustion and substitution by chlorine in the presence of ultraviolet light at room temperature
• describe the chemistry of the following classes of compounds: — alkenes (exemplified by ethene) in terms of combustion and addition reactions with bromine (in CCl4) and hydrogen (using Ni catalyst)
• describe the chemistry of the following classes of compounds: — halogenoalkanes (exemplified by bromoethane) in terms of substitution reaction to alcohols (using NaOH(aq), heat) and elimination reactions to alkenes (using NaOH in ethanol and heat)
• describe the chemistry of the following classes of compounds: — alcohols (exemplified by ethanol) in terms of combustion, oxidation to carboxylic acids (using acidified K2Cr2O7 or acidified KMnO4 and heat) and elimination to alkenes (using concentrated H3PO4 catalyst and heat)
• describe the chemistry of the following classes of compounds: — aldehydes (exemplified by ethanal) and ketones (exemplified by propanone) in terms of their reduction to primary and secondary alcohols respectively (using LiAlH4, or using H2(g), Ni catalyst) and oxidation of aldehydes to carboxylic acids (using acidified K2Cr2O7 or acidified KMnO4 and heat)
• describe the chemistry of the following classes of compounds: — carboxylic acids (exemplified by ethanoic acid) in terms of: - reaction with alkalis and carbonates to form salts, - condensation with alcohols to form esters (in the presence of concentrated H2SO4 catalyst), and with amines (exemplified by ethylamine) to form amides (in the presence of dicyclohexylcarbodiimide, DCC) [knowledge of structure of DCC is not required]
• describe the chemistry of the following classes of compounds: — esters (exemplified by ethyl ethanoate) and amides (exemplified by ethanamide) in terms of hydrolysis with aqueous acid (or aqueous alkali) and heat [detailed conditions involving specific temperature and pressure values are not required]
• describe the chemistry of the following classes of compounds: — amines (exemplified by ethylamine) with aqueous acid to form salts
• recognise polymers as macromolecules built up from monomers, with average relative molecular mass of at least 1000 or at least 100 repeat units
• classify and explain the difference between addition and condensation polymers
• describe proteins as examples of condensation polymers made up of α-amino acids as monomers, forming peptide (amide) bonds
• describe the hydrolysis of proteins using aqueous acid (or aqueous alkali) and heat
• describe the specific bonds or interactions that stabilise the three-dimensional structure of a protein: hydrogen bonding, intermolecular forces and ionic linkages [knowledge of the specific levels of structure of proteins, including a-helix and β-pleated sheet, is not required.]
• explain denaturation of proteins by extremes of temperature and pH changes, in terms of disruption of the bonds or interactions that hold the three-dimensional structure of the proteins (see also LO 7(i))
• apply knowledge of the loss and formation of three-dimensional structure to interpret real-world phenomena such as heating of egg whites and addition of vinegar to milk [candidates are not required to identify the proteins in the substances.]
• classify and explain the difference between thermoplastic (linear, as exemplified by poly(ethene)) and thermosetting (cross-linked, as exemplified by poly(diallyl phthalate)) polymers with reference to structure, bonding and the following properties: — softening behaviour, including capacity to be recycled
• classify and explain the difference between thermoplastic (linear, as exemplified by poly(ethene)) and thermosetting (cross-linked, as exemplified by poly(diallyl phthalate)) polymers with reference to structure, bonding and the following properties: — rigidity
• classify and explain the difference between thermoplastic (linear, as exemplified by poly(ethene)) and thermosetting (cross-linked, as exemplified by poly(diallyl phthalate)) polymers with reference to structure, bonding and the following properties: — strength
• describe and explain the types of structure and bonding in relation to the properties and uses as exemplified by the following: — low density poly(ethene) (LDPE) in plastic bag and high density poly(ethene) (HDPE) in plastic bottles in relation to LDPE being softer and more flexible, and HDPE being harder and stiffer
• describe and explain the types of structure and bonding in relation to the properties and uses as exemplified by the following: — polyester and polyamide as fabric in relation to polyester (exemplified by poly(ethylene terephthalate) (PET)) as a fabric that is slightly less prone to creasing than polyamide (exemplified by nylon 6,6)
• describe and explain the types of structure and bonding in relation to the properties and uses as exemplified by the following: — poly(vinyl alcohol) (PVA) as a water-soluble polymer in eye drops and poly(vinyl chloride) (PVC) as a water-resistant polymer used in raincoats
• describe and explain the types of structure and bonding in relation to the properties and uses as exemplified by the following: — poly(propene) (PP) container instead of one made from poly(ethylene terephthalate) (PET) to store strongly alkaline cleaning solutions due to hydrolysis of PET
• predict physical properties of polymer from its structure
• recognise that poly(alkenes) are chemically inert and can therefore be difficult to biodegrade (see also 9(g)(i))
• recognise that polyesters and polyamides are generally biodegradable by hydrolysis (see also 9(g)(vii))
• recognise that materials are a finite resource and the importance of recycling plastics, considering the economic, environmental and social factors.