MediumChemistryHigh School (11–12)Organic Compounds with Functional Groups › Aldehydes, Ketones and Carboxylic AcidsNumerical

1.20 g of acetophenone (120.15 g/mol) is reduced by the Wolff-Kishner method to ethylbenzene…

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$1.20\ \text{g}$ of acetophenone ( $120.15\ \text{g/mol}$ ) is reduced by the Wolff-Kishner method to ethylbenzene ( $106.17\ \text{g/mol}$ ). One mole of nitrogen forms for each mole of ketone. The gas is collected at $298\ \text{K}$ and $101.3\ \text{kPa}$ . Find the amount of ketone, the mass of ethylbenzene at a $100\ \%$ yield, and the volume of nitrogen. Take $R = 8.314\ \text{kPa L/(mol K)}$ .

Need a reminder? The key ideaShow

Wolff-Kishner and Clemmensen turn C=O into CH $_2$ (base and acid). Perkin: ArCHO, (CH $_3$ CO) $_2$ O and CH $_3$ COONa at 453 K give ArCH=CHCOOH. Haloform: CH $_3$ CO- with 3 X $_2$ and 4 NaOH gives CHX $_3$ and the carboxylate with one carbon fewer. A crossed aldol with an aldehyde that has no alpha hydrogen is a Claisen-Schmidt reaction. For a gas, $V = nRT/P$ with $R = 8.314$ kPa L/(mol K).

The worked solution

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