5. Speaking.

1. Work with a partner. Here are his answers. Ask him questions.

--- ___________________________?

• Chemistry is the study of different kinds of matter.

--- ___________________________?

• All samples of a specific substance show the same properties.

--- ___________________________?

• All pure substances can be divided according to their composition into two main classcs: elements (metals and non-metals) and com­pounds.

--- ___________________________?

• Laboratory investigations of compounds follow two general tech­niques - analysis and synthesis.

--- ___________________________?

• Nowadays the word assay can be applied to analysis in general, but in particular it means the analysis of pharmaceutical and official drugs.

--- ___________________________?

• The quantitative analysis is determination of the amount of sub­stances present.

--- ___________________________?

• The qualitative analysis is detection of the kind of substances pres­ent.

2. Speak on the following items:

• chemical analysis;

• the necessity of detecting constituent substances in everyday life;

• modern equipment at chemical laboratories.

Chemical compounds

1. Active vocabulary.

rhubarb		ревінь
vinegar		оцет
derivation		походження
sour		кислий
hydrochloric		соляний
significant		значний
to neutralize		нейтралізувати
particle		частка
to stipulate		обумовлювати
digestion		травлення
slippery		слизький
property		властивість
to vanish		зникати

2. Lead in. Work with the text.

1. Match the synonyms:

1. acute	a. peculiarity
2. significant	b. sharp
3. bitter	c. to give away
4. to determine	d. to get
5. property	a. to combine with
6. to obtain	f. to establish
7. to yield	g. harsh
8. to react	h. major

2. Match each word from column A with its opposite from column B.
1. acute	a. to destruct
2. sour	b. to oppose
3. sharp	c. to leave
4. to yield	d. mild
5. opposite	e, chronic
6. to join	f. sweet
7. to vanish	g. same
8. to obtain	h. to appear