3 Part One. The Predicate

Lesson 10
GRAMATIKA: Формы н употребление сослагательнofо наклонения
Section I

Ex. 1. Pronouncc the following words:

b) laboratory [lo'borstn], curiosity [.kjuorf DSiti], available [o'veil obi], exhibit [tg'zibit], anhydrous [asn'haidrds], dilute [dai'lu:t], equation [i'kwei/эп], hydroxide [hai'droksaid], residue [‘rezidju:], approximately [o'proksimoth]

Ex. 2. Read the following words and say what Russian words help to understand their meanings:

gram, laboratory, mineral, per ccnt, characteristic, group, oxide, combination, halide, stable, hydrate, electrodc, potential, conccntratc, reaction, metallic, volt, spectral, line, analysis, method, extract, zinc, indium, material, collect, mass, cadmium, filter, filtrate, result, neutralize, basic, sulphite

Ex. 3. Pay attention to the following way of word-building:

Ex. 5. Define the meaning of the italicized words.

1. No commercial applications of indium were attemptedfor many years. 2. Their attemptto obtain pure indium was a success. 3. The available supplyof indium at that time was only one gram. 4. Some compounds of indium were suppliedfor further analysis. 5. In(OH)₃ is precipitatedfrom an indium salt solution. 6. When KOH was added to an indium salt solution, a precipitateof In(OH)₃ was formed.

Text 10 A
Indium
Indium was regarded as a laboratory curiosity for many years and no commercial applications were attempted until 1924. It would hardly be possible to think of its application, for the available supply at that time was only one gram, with no immediate prospects of more.Indium seldom occurs in a mineral in quantities over 0.1 per ccnt.

Several methods of extracting indium from its ores should have been considered. According to one of them, indium-bearing zinc metal was treated with a quantity of dilute H₂SO₄which would dissolve almost all the material, leaving a residue of zinc. On this residue there was collected a spongy mass composed of lead, copper, cadmium, tin, arsenic, iron, and indium. Nitric acid was used to dissolve the spongy mass, after which the solution was evaporated with sulphuric acid. Lead sulphate was left behind on the filter.

The filtrate was treated with NH₃(aq) to precipitate In(OH)₃ and Fe(OH)₃ which were dissolved in HCl. The resulting solution was approximately neutralized and boiled with NaHSO₃, which precipitated the basic sulphite, In₂(SO₃)₃ ·In(OH)_3· 5H₂O. The basic sulphite was dissolved in sulphuric acid and pure In(OH)} was obtained by the addition of NH₃(aq).Indium exhibits properties characteristic of the aluminium group.

Indium burns in air with a blue flame to form the scsquioxidc, In₂O₃. If it were heated in the presence of galogens or sulphur, direct combination would take place. In each case indium goes to its highest oxidation state.

The other halides (InX and InX₂, where X is a galogen) have been prepared, with the possible exceptions of InF and InF₂. Only the halides, InX₃, are stable in the presence of water. There are three tri-fluorides of indium, the hydrates of the compositions InF₃·3H₂O and InF₃·9H₂O and the anhydrous salt, InF₃. Most indium compounds are soluble in water.
Words and Word-Combinations to Be Memorized

acetic acid, addition, almost, aluminium, analysis, anhydrous, approxi­mately, attempt, available, basic, boil, case, collect, compose, composition, dilute, direct, electrodc, equation, evaporate, cxccption, exhibit, extract, filter, fluoride, halide, hardly, hydroxide, indium, laboratory, lie, mass, material, most, nitric acid, oxidation, per ccnt, potential, precipitate, prevent, regard, residue, salt, seldom, scries, sulphite, soluble, supply, take place, volt

Ex. 6. Give the Uzbek equivalents for the following:

attempt applications, regard smth. as, hardly, be available, immediate prospects, over 1 per ccnt, exhibit properties, bum with a blue flame, in the presence of, take place, in each ease, oxidation state, with the cxccption of, be soluble in water, in the electromotive series, an electrodc potential, dilute acid, react with the evolution of hydrogen, together, concentratedacid, acetic acid, according to the equation, to have some cfTcct on smth., to dissolve almost all the material, the resulting solution

Ex. 7. Give the English equivalents for the following:

Ko'p yillar davomida, bir foizdan ortiq miqdorda, bir necha usullarni, suyultirilgan sulfat kislotani, filtrdagi deyarli barcha moddalarni, natijada olingan eritmani, xarakterli xususiyatlarni namoyish etadigan, havoda bir hovuch, to'g'ridan-to'g'ri ulanishni ko'rib chiqish deyarli mumkin emas. , har bir holatda, biror narsa bundan mustasno, suv borligida, suvsiz tuz, ko'p birikmalar, konsentrlangan kislota, tenglama bo'yicha (tenglama bo'yicha), spektral tahlil

Ex. 8. Fill in the blanks with prepositions where necessary.of, at, in, between, with, from, according to, for

1.... many years indium was regarded as a laboratory curiosity. 2. There are several methods ... extracting ... indium ... its ores. 3 .... one ... the methods... obtaining indium, indium-bearing zinc is treated... dilute H;S04.4. Indium exhibits properties characteristic... the aluminium group. 5. Indium bums ... air ... a blue flame. 6. If indium is heated ... the presence ...galogens or sulphur, direct combination takes place. 7 each case indiumis ... its highest oxidation state. 8. Only the halides, InX3, are stable ... the presence ... water. 9. Most indium compounds are soluble ... water. 10. Indium lies... iron and tin ... the electromotive series. 11. Characteristic spectral blue lines ... indium occur... 451.1mμ and 410.1 mμ

Ex. 9. a) Mind:

No article is used before nouns denoting some branch of science, the names of chemical elements and the word school.

Examples: 1. My younger sister goes to school.

2. While at school 1 liked chemistry best.

3. Indium has an electrodc potential of -+0.336 volt.
Ex. 10. Translate the sentences into Uzbek, paying attention to the subjunctive mood.

1. There would be no life without such elements as carbon, oxygen, hydrogen, etc. 2. It is necessary that the substances be pure. 3. The teacher suggested that the equation of the reaction be written on the blackboard.4. The solution is diluted lest it be very strong. 5. They would do it once more if they had time. 6. The condition was made that the reaction should procccd slowly. 7. He should have told us about the new time-table. 8. She should have done it yesterday but she didn't know that her results were not accurate. 9. Heating or cooling would affect the state of water, but not its composition. 10. Dry gas would occupy less volume. 11. It would be difficult to find a more abundant element than oxygen. 12. The corrosion would procccd much more rapidly in the presence of oxygen. 13. We would begin the calculation but We have no all the necessary data. 14. You should have known that these are inflammable substances. 15. They should have described the properties of the substances that were obtained. 16. It would be true to say that experiment is the foundation of chemistry. 17. The new apparatus would have given more accurate results. 18. It is essential that water should be turned into vapour. 19.1 wish she were right. 20.1 should have asked the teacher but I could not come to the seminar. 21. They suggest that the experiment be started at once.

Ex. 11. Translate the sentences into English.

1. Indiy tabiatda juda kam miqdorda uchraydi. 2. Indiyning xususiyatlari III guruh elementlariga xosdir. 3. Indiy havoda kuyadi va In₂O₃ oksidini hosil qiladi 4. Indiyning ko'pgina birikmalari suvda eriydi. 5. Suyultirilgan xlorid kislotasi indiy bilan reaksiyaga kirishib vodorod hosil qiladi. 6. Sirka kislotasi indiyni eritmaydi. 7. Spektral tahlil indiy ko'k chiziqlarini ko'rsatadi.

Ex. 12. Make up questions to the italicized parts of the sentences.

1. Indium lies between iron and tin in the electromotive series (2).

2. Two reactions are possible with concentrated sulphuric a cid (3).

3. Severalmethods of extracting indium from its oresare possible (2).

Ex. 13. Answer the following questions:

1 . What is the occurrence of indium in nature? 2. What properties does indium exhibit? 3. What can you say about commercial applications of indium? 4. What kind of oxide does indium form? 5. What compounds of indium and the galogens are known? 6. In what way does indium react with sulphuric acid? 7. What does the spectral analysis show?