Lesson 19

  1. Lesson 10
  2. Lesson 11
  3. Lesson 12
  4. Lesson 13
  5. Lesson 14
  6. Lesson 15
  7. Lesson 16

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Section I

Ex. 1. Practise your pronunciation.

a) originally [o'ridsonoh], stereochemistry [.stena'kemistn], final [Tainol], postulate [ 'postjoht], draw [dn>:], concisc [kan'sais], qualitative [' kwolitotivj, numerous [ ' njurmoros], electronic [llek'tronik], culminate [ 'kAlmineit], completion [kam'pli: Jan], emphasize [' cmfosaiz], clarify [ 'klxnfai], isomer [' aisomo]

b) thc ^ 'structurc ^ ofNinoIccules, compo'sitionwofwa \ substance, the " 'nature ^ ofjhcj-cNaction, thcv'theorywofs. valence, 'after0theudis \ covery an ^ elec'tronicNtheoiy, 'thesej ^ deas, all ^ of ^' thcscSstudcnts

c) The 'nature of the' bond | was com'plctcly un \ known.

Ex. 2. Pay attention to the structure of the following words. Translate them into Russian.

a) stereotype, stereochemistry, stereophonic, stcrcoscopc, stereometry

b) dihedral, trihedral, tetrahcdral, pentahedral, octahedral

c) neighbourhood, childhood, boyhood, manhood

Ex. 3. Define the meanings of the word part in the following sentences:

1. A theory usually involves some idea about the nature of some part of the Universe. 2. One of the most valuable parts of the chcmical theory is the periodic law. 3. Hard alloys arc applied to the surfaces of metal parts, increasing the life of the parts many times. 4. The substances taking part in the reaction should be pure. 5. Partly, you can find the ncccssary information in this monograph. 6. V. Tikhonov played the part of Bolkonsky

in the War #nd Peace. 7. They parted at 6 o'clock. 8. The firm was only a partial success. 9. Under certain conditions, hydrogen atoms in this compound may be in part substituted by sulphur.

Ex. 4. Find the predicate, the subject and the object in the following sentences:

1. In the nineteenth ccntury the valcncc bond was represented by a line drawn between the symbols of two chcmical elements. 2. Lewis * paper written in 1916 is considered to be the basis of the modern clcctronic theory of valcncc. 3. These ideas were further developed by many investigators.

Text 19 A




Text 9 | Fluorine | Lesson 10 | Text 10 | Lesson 11 | Fascinating Phosphorus | Modifications of Phosphorus | Lesson 12 | Chemical Symbols for Representing Compounds | Weight of 12 atom of carbon 12 |

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