This question is about the analysis of organic food preservatives.
Compound F is a cis stereoisomer of an unsaturated acyclic monocarboxylic acid with the general formula CnH2n−1COOH\text{C}_n\text{H}_{2n-1}\text{COOH}CnH2n−1COOH.
A quality control chemist plans to identify acid F by carrying out a precise volumetric titration.
The chemist first prepares 250.0 cm3250.0\text{ cm}^3250.0 cm3 of a standard solution of 0.240 mol dm−30.240\text{ mol dm}^{-3}0.240 mol dm−3 NaOH\text{NaOH}NaOH for the titration.
The chemist is provided with solid NaOH\text{NaOH}NaOH, distilled water, and standard laboratory glassware.
Describe how the chemist would prepare this standard solution, providing the necessary quantitative calculation of the mass of NaOH\text{NaOH}NaOH required, along with details of the apparatus and the steps of the experimental method.
The chemist prepares a 250.0 cm3250.0\text{ cm}^3250.0 cm3 aqueous solution containing exactly 5.472 g5.472\text{ g}5.472 g of acid F.
The chemist titrates 25.0 cm325.0\text{ cm}^325.0 cm3 aliquots of this solution of F with the prepared 0.240 mol dm−30.240\text{ mol dm}^{-3}0.240 mol dm−3 NaOH(aq)\text{NaOH(aq)}NaOH(aq) delivered from a burette.
1 mol1\text{ mol}1 mol of NaOH\text{NaOH}NaOH reacts stoichiometrically with 1 mol1\text{ mol}1 mol of F.
The mean titre of NaOH(aq)\text{NaOH(aq)}NaOH(aq) obtained is 20.00 cm320.00\text{ cm}^320.00 cm3.
Analyse these titration data to determine the molecular formula of F, and hence deduce two possible structures for the cis stereoisomer of organic acid F.
