Mendeleyev’s Contribution to chemistry

Learn the new lexical material:

in spite (of)	не зважаючи (на)
undoubtedly	без сумніву
to suffer changes	зазнавати змін
subsequent years	наступні роки
to fully realise	усвідомлювати повністю
to point out	указувати, підкреслювати
to predict	передбачати
comprehensive work	вичерпна, глибока робота
remarkable agreement of properties	визначне узгодження властивостей
justification	підтвердження
faith	віра
to be proud (of)	гордитися
series	серія, низка, ряд, цикл

1. Read and translate the text:

In spite of the importance of the contributions that had been made earlier, the greatest portion of credit for the development of the Periodic System must undoubtedly go to the Russian scientist, D. I. Mendeleyev. The understanding that the properties of the elements can be represented as periodic functions of their atomic weights made possible classification that has suffered few significant changes in the subsequent years.

In March of 1869 D. I. Mendeleyev published his first description of the Periodic System in which he gave the arrangement of the elements in terms of their increasing atomic weights. He fully realized the importance of this periodicity. In his first article D. I. Mendeleyev pointed out the similarities of a number of properties of certain elements and changed the order of atomic weights where necessary in order to have the group similarity. D. I. Mendeleyev left vacant positions in his table for yet undiscovered elements and expressed the opinion that the chemical and physical properties of the elements would be discovered, as he predicted, from their positions in the table.

In the summer of 1871 D. I. Mendeleyev published a more comprehensive work and called it the Periodic Law. At this time he presented the more familiar form of the Periodic Table and although it differs somewhat from the one we use today, it is in general the same. In his publication of 1871 D. I. Mendeleyev used the periodic character to predict the properties of the elements which would be later described as those of scandium, gallium, and germanium. The remarkable agreement of the properties of these elements as they had been described by Mendeleyev and those that were observed later is without doubt a complete justification of D. I. Mendeleyev's faith in his Periodic Law.

In December 1945 Glenn Seaberg made his first publication of a Periodic Table which described a new actinide series beginning with actinium. He said that American scientists were proud and happy to honor the name of D. I. Mendeleyev by calling element 101 "mendelevium".

 

2. Choose the most suitable title to the text out of the given ones:

1. History of Scientific Discoveries.

2. Mendeleyev’s Contribution to Chemistry.

3. Elements of the Periodic Table.

4. The Periodic System of Elements.

 

3. List the points of the given plan in the order of events they occur in the text:

1. Advent of the Periodic Law.

2. Discovery of "Mendelevium".

3. Similarities of Elements' Properties.

4. The Inventor of the Periodic System of Elements.

 

Write out the main sentence(s) of each logical part and translate them into Ukrainian.

 

Combine the sentences you've written out into a summary. Then rewrite them in your own words, omitting unnecessary details.

6. Translate the following sentences into English:

1. Професор сказав, що експеримент проводиться для демонстрації його доповіді.

2. Студенти сказали, що дізналися про нове відкриття на семінарі.

3. Викладач знав, що декілька студентів стануть дослідниками.

4. Учені були впевнені, що деякі відкриття вплинули на наукові погляди Менделєєва.

5. Декілька прогресивних учених розуміли, що існує певна система елементів.

6. У своїй книзі Б. Н. Конарєв доводить, що у стародавні часи люди знали тільки ті речовини, які були їх необхідні для життя.

7. Арабські алхіміки уже в ІХ – Х ст. вважали, що всі речовини можна поділити на органічні та неорганічні.

8. Лавуазьє відповів на ті питання, на які не могли знайти відповідь учені кількох поколінь.

9. Викладач розповів на лекції, який внесок зробив Берцеліус у неорганічну хімію.

10. Ми знаємо, що Берцеліус був автором декількох підручників з хімії.

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