OZ Section 3 (a), (b), 11 hours Experiments providing Main chemical Intermolecular – – (c), (d), (j), (k), (l), (m), (n), evidence for the formation bonding; haloalkanes; nucleophilic (q) of intermolecular bonds substitution reactions; the sustainability of (including hydrogen bonds) the ozone layer. A consideration of CFCs for example . – and HFCs then provides Accurate use of the following will be the introduction to the Experiments to illustrate the required: for electronegativity, substitution and chemistry of haloalkanes, relative reactivity of the nucleophile. including nucleophilic haloalkanes for example . – Discussion of the boiling points of halogens substitution, and Using SN2 as a model for should be included. intermolecular bonding. reaction mechanisms and Learner should be able to use the SN2 modelling the depletion of mechanism to explain nucleophilic ozone levels (HSW1). substitution reactions. Knowledge of the SN1 Evaluating experimental mechanism isn’t required, nor the terms SN1 evidence linking rate of or SN2, although these provide a good point haloalkane hydrolysis with for stretch and challenge. bond enthalpy and polarity A full discussion of the formulae, properties (HSW6). and reactions of haloalkanes is required. Explaining and evaluating Amines are introduced here. the role of in the stratosphere and the effect of haloalkanes on ozone (HSW8, 11, 12). What’s in a Medicine (WM) –
OZ – Section 3 – (a), (b), (c), (d), (j), (k), (l), (m), (n), (q) A consideration of CFCs and HFCs then provides the introduction to the chemistry of haloalkanes, including nucleophilic substitution, and intermolecular bonding. 11 hours Experiments providing evidence for the formation of intermolecular bonds (including hydrogen bonds) – for example . Experiments to illustrate the relative reactivity of the haloalkanes – for example . Using SN2 as a model for reaction mechanisms and modelling the depletion of ozone levels (HSW1). Evaluating experimental evidence linking rate of haloalkane hydrolysis with bond enthalpy and polarity (HSW6). Explaining and evaluating the role of in the stratosphere and the effect of haloalkanes on ozone (HSW8, 11, 12). Main chemical Intermolecular bonding; haloalkanes; nucleophilic substitution reactions; the sustainability of the ozone layer. Accurate use of the following will be required: for electronegativity, substitution and nucleophile. Discussion of the boiling points of halogens should be included. Learner should be able to use the SN2 mechanism to explain nucleophilic substitution reactions. Knowledge of the SN1 mechanism isn’t required, nor the terms SN1 or SN2, although these provide a good point for stretch and challenge. A full discussion of the formulae, properties and reactions of haloalkanes is required. Amines are introduced here. What’s in a Medicine (WM) –