2015-05-13
476
alkaline-earth metals - щелочноземельные металлы
beryllium - бериллий
calcium - кальций
strontium - стронций
barium - барий
to refer to - относиться, ссылаться
size - размер
charge - заряд
single charge - единичный заряд
to favour - благоприятствовать
lattice energy - энергия кристаллической решетки
radium - радий
amphoteric - амфотерный
surface film - поверхностная пленка
solubility - растворимость
Exercise 2. Answer the following questions.
1. What elements belong to alkaline-earth metals?
2. What is your understanding of the term “alkaline - earth”?
3. What element does beryllium resemble?
4. When can one observe a fairly regular increase in atomic and ionic radius?
5. What does the overall energy change favour?
Exercise 3. Put questions to the bold-typed words.
1. Beryllium has anomalous properties.
2. Beryllium has a high melting point.
3. The hydroxides decompose on heating to give the oxide.
4. The oxides of the metals show the increasing ionic character.
5. Beryllium has higher boiling and melting points than calcium.
6. The standard electrode potentials show a regular small decrease from magnesium to barium.
7. Regular changes take place down the group.
8. Alkaline-earth metals react with water and oxygen.
9. One can observe a decrease in first and second ionization energies down the group.
10. Compounds contain univalent ions.
11. All alkaline-earth metals have a characteristic electron configuration.
12. There are three electrons in the outer shell.
Exercise 4. Give the equivalents for the following words and make up sentences with them: univalent, compound, lattice energy, sparingly soluble, solution, amphoteric, to favour, charge, size, single charge, to refer to, surface film, solubility, reducing agent, regular.
