The Periodic System

The periodic law of elements discovered by the great Russian scien­tist Mendeleyev is one of the basic laws of chemistry.

In 1869 Mendeleyev published his work, describing an arrangement of the elements that has since become known as the Periodic system. He ar­ranged the elements in the order of their atomic weights, starting from the lowest and showed that: 1) elements, if they are arranged according to their atomic weights, exhibit the periodicity of properties; 2) elements, which have similar chemical properties, have atomic weights which are of nearly the same value, or which increase regularly; 3) the arrangement of the ele­ments in the order of their atomic weights corresponds to their valences and to some extent to their chemical properties (lithium, barium, carbon, nitrogen, oxygen, iron); 4) widely diffused elements have small atomic weights; 5) the magnitude¹ of the atomic weight determines² the character of the element, just as the magnitude of a molecule determines the character of a compound; 6) the discovery of many as yet unknown elements, whose atomic weights will be between 65-75, can be expected; 7) certain charac­teristic properties of the elements can be foretold³ from their atomic weights.

The elements in the Periodic system fall into seven periods on the one hand and nine groups on the other hand.

In each group, the elements show a similarity in their properties.

When Mendeleyev first arranged his Periodic Table he left two gaps⁴ between zinc and arsenic in the fourth period and another gap between cal­cium and titanium. A few years later these three elements were discovered: gallium, germanium and scandium.

1. magnitude — величина;

2. determine — визначати;

3. can be foretold — можна передбачити;

4. gap — пропуск, пробіл

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Diana — the People's Princess

She was the most watched woman in the world — until tragedy hap­pened in Paris.

She was "beautiful, of course; she was young, and she was royal. In the shock of her death, the world struggled to know the contradictory sources of Diana's appeal; the Princess of Wales was both pop icon and the mother of kings, a very modern woman who owed her fame to me most archaic of institutions. Her secret was that she was all these things. Diana was - capable of profound change — both in her private fife and in her public image.

When she married Charles in 1981, Diana personified the fairy-tale version of royalty. The awkward teenager got the world's most famous bachelor. In time, the public revealed the truth. This was not a marriage lifted from the pages of a romantic novel but an all-too-modern, deeply troubled one.

By the time Charles and Diana separated in 1989, her moment as an icon of young beauty and motherhood was over. What came next was truly surprising. A person who had led a life of privilege turned out to be a com­mon woman, boldly embracing АIDS babies," The person who had been raised to stay in her husband's shadow gave a television interview in which she rejoiced in being a «strong woman».

When she first appeared in 1980, she brought light to a drab Old British society that had lost both an empire and its self-confidence. When she died, she had become the symbol of the New British — stylish, cosmo­politan, liking the town but hating the country. She could change other people's attitudes.

«She was the People's Princess», said Tony Blair, Britain's Prime Minister, «and that's how she will remain in our hearts and memory forever»,

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