Vocabulary

alkaline-earth metals - щелочноземельные металлы

beryllium - бериллий

calcium - кальций

strontium - стронций

barium - барий

to refer to - относиться, ссылаться

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nivalent - одновалентный

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.

Exercise 5.

1. Match the beginnings of the sentences with the endings.

1. Beryllium has a) down the group.

2. Alkaline –earth metals react with b) anomalous properties.

3. Calcium c) high.

4. Ba hydroxide is d) a very soluble.

5. Alkaline - earth metals’ properties increase e) is useful for children.

6. Solubilities of salts can decompose g) on heating.

7. T

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   he boiling point of Be is f) water.

8. The overall change h) 0.112 nm.

9. The atomic radius of Be is g) favours the formation

of divalent compounds.

2. Grammar and spelling quiz: find and correct the mistakes:

1. Be have anomalous propertyes.

2. The atomic radius (0.112 nm) of Be are more less that those of magnesium (0.16 nm).

3. To general, the is soluble salts of the alkali-earthy elements if the anion had an single charge.

4. These elements reats to water.

5. We is studying the compounds contain univalent ions.

6. An standard electrode potentials a regular decrease in magnesium to barium show.

3. Chemical quiz: Are these sentences true or false?:

1. Carbon is a non-metal.

2. Na is an alkaline-earth metal.

3. The oxides and hydroxides of the alkaline-earth metals show the decreasing atomic character in moving down the group.

4. The hydroxides of the alkali metals are weakly alkaline.

4. Finish the sentences:

1. Alkaline - earth metals are …

2. Beryllium resembles …

3. Alkaline-earth metals react with …

4. The third ionization energies are much …

Exercise 6. Give the explanations for the following words: ion, solution, property, reducing agent, oxide, amphoteric, alkaline-earth.

Exercise 7. Make the following sentences negative and interrogative.

1. The overall energy change favours the formation of divalent compounds.

2. The stability of the salts of oxo acids increases down the group.

3. Other regular changes take place in moving down the group from magnesium.

4. The oxides and hydroxides of the metals show the increasing ionic character in moving down the group.

5. Be density lies between those of calcium and strontium.

6. The elements are sometimes referred to as the alkaline earths.

7. The solubilities of the salts of a particular acid tend to decrease down the group.

8. Alkaline-earth metals have many uses.

9. The standard electrode potentials show a regular trend.

Exercise 8. Project work:

1. D

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   escribe any alkaline-earth metal on the following plan:

1. boiling point;

2. melting point;

3. atomic number;

4. relative density;

5. valence;

6. Is it a metal or non-metal?;

7. What group does it belong to?;

8. colour;

9. odour

10. Where is it used ?;

11. What substances does it react with ?;

12. What chemical compounds does it have ?.

2. Choose any two alkali elements and compare them on the following plan using comparative and superlative degrees:

6. melting point;

7. boiling point;

8. relative density;

9. atomic and ionic radius;

10. relative atomic mass.