Химия Open the brackets choosing the suitable word and translate them into просмотров - 225
Answer the questions
1. What is nuclear fission?
2. How was nuclear fission discovered?
3. What nuclei ordinarily disintegrate into particles of disparate mass and charge?
4. What is the larger particle in these cases?
5. What element was bombarded with slow-moving neutrons?
6. What was found when uranium was bombarded with slow-moving particles?
7. What was verified by direct calorimetric measurement?
8. How many calories can be produced by the complete fission of one pound of
9. What elements are capable of undergoing fission when exposed to slow neutrons?
10. What elements are considered to be important sources of heat and energy in the
2. Translate the sentences into Ukrainian:
1. The new method appeared to be very tedious and time-consuming. 2. The atoms of unconfined elements proved to be electrically neutral. 3. Elements composed of atoms containing only one or two valence electrons prove to form positive ions by giving up electrons during their reactions. 4. This new element has been discovered to be very useful. 5. They knew this new element to have been discovered to be very useful. 6. Many of the substances determined to be soluble will be carefully investigated. 7. Zinc and cadmium are used widely to protect iron and steel from rust. 8. During the burning of coal there appears to be a loss of weight. 9. The changes reported to take place are shown in this table. 10. These changes were found to follow certain rules. 11. The Beta rays were shown to be negative particles. 12. The element helium is known to have been discovered in the sun. 13. Organic chemistry is known to be defined as the chemistry of compounds containing carbon. 14. The experimenter knew this substance to be absolutely pure. 15. The procedure to be used for this work must be very accurate.
1. The capture of neutrons by the atoms of uranium, thorium and protactinium is known (to result from, to result in) forming of heavier isotopes. 2. I can’t start working (till, until) he comes, as he has got all the necessary figures. 3. (Only, the only) chemicals examined in our laboratory should be used in our work. 4. The only method available for this work (till, until) recently was the gravimetric method. 5. Having carried out a number of investigations, Fermi succeeded in creating the (natural, artificial) isotopes. 6. Since the atomic nuclei of radioactive elements differ from (that, those) of nonradioactive elements only in the number of protons and electrons which they contain, it is believed that radioactivity (results in, results from) instability of certain atomic nuclei. 7. Ammonium salts greatly resemble (those, that) of the alkali metals especially (that, those) of potassium. 8. The positively charged particles are known to be called alpha-rays, (those, that) negatively charged are called beta-rays. 9. The ordinary heterogeneous reaction is (that, those) involving solid crystals with liquid or gaseous reactants. 10. The properties of the oxide of deuterium are similar to (those, that) of water but still there are small differences.
Answer the questions EXERCISES1. What is nuclear fission? 2. How was nuclear fission discovered? 3. What nuclei ordinarily disintegrate into particles of disparate mass and charge? 4. What is the larger particle in these cases? 5. What element was bombarded with slow-moving neutrons? 6. What was found when uranium was bombarded with slow-moving particles? 7. What was verified by direct calorimetric measurement? 8. How many calories can be produced by the complete... [читать подробенее]