III.7. Прочтите описания следующих химических реакций и назовите тип каждой реакции.

a) This reaction, the opposite of oxidation, has very wide applicationns in the production of pharmaceuticals. Examples of reducing agents are aluminum amalgam, hydriodic acid, hydrogen and a catalyst, hypophosphorus acid, lithium aluminum hydride, metal and acid, sodium and alco­hol, stannous chloride, and zinc dust and water. Reduction is employed in the synthesis of racemic menthol, an anti-itching agent. It is produced by the catalytic hydrogenation of the aromatic analogue, thymol, or of the saturated ketone, menthone, or of the unsaturated ketone, pulegone.

b) This chemical reaction can only take place with unsaturated com­pounds, but the addition products vary greatly in nature. The mode of ad­dition, where there are two possibilities, is determined by the structure of the unsaturated compound and the mechanism of addition.

The anesthetic drug halothane is manufactured from trichloroethyl-ene by an addition reaction with hydrogen chloride. The product is treated with hydrogen fluoride; reaction with bromine then gives halothane.

The manufacture of the anesthetic drug trichloroethylene involves, as a first step, the addition of chlorine to acetylene, followed by dehydro-halogenation.

c) Medicinal nitro compounds are invariably aromatic carbocyclic or heterocyclic derivatives. These are usually nitrated with a mixture of con­centrated sulfuric acid and concentrated or fuming nitric acid (mixed acid). Other nitrating agents include oxides of nitrogen and acetyl ni­trate, CH₃CO₂NO₂.

Nitrofurantoin is prescribed as a urinary antiseptic and provides an example of nitration. Furfural is reacted with acetyl nitrate, and the re­sulting triacetate is treated with pyridine to give 5-nitro-2-furaldehyde diacetate. This is condensed (with elimination of acetic acid) with 1-ami-nohydantoin to yield nitrofurantoin.

III.8. Начертите схему, представляющую разнообразие химических соединений. Прокомментируйте свою схему по-английски. Объясните принцип построения вашей схемы. Используйте следующие слова и выражения:

§ …… belong to the first category

§ for example, …

§ … such as …

III.9. Опишите химическую реакцию, которую вы проводили в ходе недавнего эксперимента на уроке химии, включая ступени реакции и последовательность ваших действий.

Используйте следующие слова и выражения:

для описания последовательности действий и ступеней реакции:

first, …. at the same time, …

second (ly), … simultaneously, …

then, … lastly, …

next, … finally, …

after that, …

для объяснения цели действий:

in order to … due to …

so that … because of …

because …