closely related to the other elements in its group. In order to understand better these groupings,
chemists have tried to fit the elements into a single plan.
One of the earlier attempts to fit the relationships among the elements into a single law was
made by John Newlands in England, who suggested the Law of Octaves.
This concept of the periodic repetition of properties was further developed by a Russian chemist
Dmitri Mendeleyev who created a Periodic Table in which he arranged the elements according to
their atomic weights and corresponding chemical properties.
D.I. Mendeleyev listed the elements known at the time (1869) in the order of their atomic
weights from the lightest to the heaviest. The elements were arranged in a table of eight columns;
elements having similar properties appeared in the same columns or groups in the table.
Mendeleyev even predicted that there were undiscovered elements and left empty spaces3 in this
table for the new discoveries.There are many ways the Periodic Table can be used. The table can
be used to find the atomic number.
The atomic weight is also indicated in the table. The orbital arrangement of electrons is
shown for each of the elements. The common oxidation states are given. For most elements these
numbers are the same as the valence numbers. The table enables us to recognize families of
elements. For example, copper (29), silver (47), and gold (79) will all be found in the same
column.
They have similar properties and are considered a chemical family. And at last the table
can be used to predict the properties of the elements. The fact that the Periodic Table can assist
in predicting properties of elements has helped in the discovery of missing elements.
Answer the following questions.
1. What certain natural groupings are there among the chemical elements?
2. What have chemists tried to do in order to understand better these groupings?
3. Who made one of the first attempts to fit the relationships among the elements?
4. Who developed the concept of the periodic repetition of properties?
5. What columns are there in the Periodic Table?
6. What did Mendeleyev predict?
B 1. Read the text statements and write if they are true ( T ) or false ( F )?
1. In order to understand better these groupings, chemists haven’t tried to fit the elements into a
single plan.
2. This concept of the periodic repetition of properties was further developed by a Russian
chemist Dmitri Mendeleyev.
3. Dmitri Mendeleyev created a Periodic Table in which he arranged the elements according to
their atomic weights.
4. D.I. Mendeleyev listed the elements known at the time (1869) in the order of their atomic
weights from the heaviest to the lightest.
5. The elements were arranged in a table of seven columns.
6. Mendeleyev even predicted that there were undiscovered elements and left empty spaces3 in
this table for the new discoveries.
C 1. Find the Russian equivalents to the following English words and word combinations.
Make three sentences with these words.
1. is closely related to a) пустое пространство
2. to fit the relationships б) установить связь
3. empty space в) недостающие элементы
4. the orbital arrangement of electrons г) тот же самый
5. the same д) расположение электронов на орбите
6. missing elements е) тесно связан
For the first time since the Cold 1)__War__, the United States is in direct competition with near peer adversaries. Under the current trajectory, Russia and China will soon employ advanced battlefield 2)technologies that exceed some of the US warfighting capabilities.To prevent this, the US 3)__has__ developed six modernization priorities for its most urgent needs: long range precision fires, next generation combat vehicle, future vertical lift, air and missile 4)_defense capabilities___, the network, and soldier 5)_network. First, the USAF will need to address the growing threat posed by both Chinese and 6)_Russian__ air defense systems. Second, particularly because of the Chinese MRBM threat to USAF bases in the Western Pacific, the USAF will need to 7)__update__ its operational resilience by investing in air defenses, by dispersing its forces to operate out of multiple smaller bases, and by operating at longer 8)__distances__outside the effective radius of these missiles. Third, the USAF will need to boost its investments in both training and munitions for striking conventional 9)_weapons__. Finally, the USAF needs to focus on increased awareness of both Chinese and Russian 10)__military___ movements.
1. At the picture Mukhtar Auezov. He was the writer. He was born in Semey region, loved the poetry of Abay Qunanbaiuli and he translated some of Whilliam Shakespeare's plays into Kazakh.
2. At the picture Gaziza Zhubanova. She was the first Kazakh female composer. Her father was a famous musician. When she was 18 she went to Moscow to study at the Gnesin Music College and the Moscow Conservatory.
3. At the picture Abilkhan Kastevev. He was the painter. His porents were poor nomads and ved in o smoll villoge in Taldykorgan Region. He was very creatve. You can see some of his paintings in the museum.