3 Part One. The Predicate

Section II
Mashq 1. Quyidagi xalqaro so’zlar nimani anglatadi?:

sort, extensively, systematically, introduction, primitive, metallurgical, restoration, nomenclature, term, natural, original

Mashq 2. Quyidagi so'zlarning ma'nolarini bilasizmi tekshiring; yo'q bo'lsa, lug'atga qarang:

prior to, combustion, phlogiston, conceive, chareoal, dual, rust

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Matnni o’qing (o’qish vaqti — 3 daqiqaы).

Original Meanings of Oxidation and Reduction
Prior to the discovery of oxygen independently by Scheelc of Sweden in 1771-1772 and by Joseph Priestley of England in 1774, combustion had been regarded to be a loss o f phlogiston. Roughly speaking, phlogiston was conceived to be a sort of materiaof fire. Lavoisier used the new knowledge to show more extensively and systematically that combustion is the combination o f the combustible substance with Priestley's “dcphlogisticatcd air”. Knowing that several products of combustion, notably those formed from sulphur, phosphorus and carbon are acidic substances, Lavoisier named the element oxygen, from the Greek for acid-former.

Lavoisier called the product formed by addition of oxygen an oxide. Therefore, it was natural to refer to the process as oxidation.

To tell the truth, long before the introduction of the term “oxidation” the term “reduction” had been used in a technical sense. Primitive man had used chareoal to win iron from ores which We call oxides. During the development of this and other metallurgical processes reduction was used, perhaps in the dual sense of bringing down the bulk of an ore to that of the metal and of a restoration. In the latter sense it was used by Paracelsus in describing the restoration of iron from rust.With de Morvcau, Berthollet and de Fourcroy — to mention only a few — Lavoisier devised the nomenclature used today. Oxides were distinguished by the name of the element combined with oxygen and by the degree of oxidation.
Mashq 3. Matnning asosiy tarkibini bir nechta jumlalarga o'z so'zlaringiz bilan tushiring.

Mashq 4. Matndagi qaysi so'z "olish" degan ma'noni anglatadi?

Mashq 5. Matnda quyidagi savollarga javob toping:

1. What was regarded as combustion before the discovery of oxygen?2. What was understood by the term “phlogiston”? 3. What was the originof the name “oxygen”? 4. In what sense was the term “reduction” used?4. What process was called oxidation?

Mashq 6. Quyidagi jumlalarni to'ldiring:

1. Oxygen was discovered independently... 2. Lavoisier showed morextensively that... 3. Lavoisier regarded an oxide as a product... 4. In metallurgy the term “reduction” meant... 5. The nomenclature used today was devised...

Section III
Ex. 1. Make up short dialogues according to the example.

Example: — Where are you from?

— I’m from Novgorod.

—Oh, I’ve never been to Novgorod, but I know it is a beautiful

town.

— Oh, yes. There are a lot of interesting places there.

Ex. 2. Respond to the following statements:

1. You know, there are several meanings of the word “reduction”.

2. However strange it may seem, the term “reduction” has several meanings, too. 3. Now reduction is regarded by chemists as the addition of electrons to a substance.
Ex. 3. Give detailed answers to the questions.

1. Why are the terms “oxide” and “oxidation” associated with the name “oxygen”? 2. In what way did the terms “oxidation” and “reduction” changc throughout the history of chemistry? 3. What do you understand by these terms now?

Ex. 4. Discuss the following topics:

1. The Esscncc of the Processes of Oxidation and Reduction.

2. The Contribution of Various Chemists into the Development of

Redox Chemistry.

3. The Aspccts of Modem Redox Chemistry.
P a r t S e v e n