1. Find equivalents:

2. Complete the sentences:

1. Scientists consider this type of chemistry to be organic because

2. Many carbon-containing compounds can be produced artificially in

3. Naturally carbon exists only in three forms

4. Organic compounds are divided

5. The carbon atoms are linked in chains in compounds and in rings in ones.

6. Substances that release hydrogen ions in water are named

7. Alkalis are substances that

8. A chemical salt is formed when

9. The pH of neutral substances, such as water, is

10. The difference of separation methods depends

11. An ordinary example of separating a substance at home is

12. Separating different parts of a compound applying electricity is

13. The electrolyte is a compound that

14. During electrolysis a compound is split into two parts because

15. The negative electrode is … and the positive one is

16. For a chemical reaction to occur

17. A solution is formed when the solute

18. If the saluted mixture is cloudy

19. A solution will not separate out if

20. Water is a clear tasteless and odourless liquid at

21. Water «wets» things because

3. Answer the questions:

1. What compounds does the organic chemistry study?

2. Where carbon containing compounds can be found and produced?

3. How many compounds known today do contain carbon?

4. Why does carbon enable to form millions of combinations of elements?

5. Why are the organic compounds divided onto aliphatic and aromatic ones?

6. What do the chains of aliphatic compounds contain?

7. What happens if acids and alkalis are mixed?

8. What does the interdependence of acids, alkalis and pH consist in?

9. What is the essence of separation?

10. Where can we observe filtration at home?

11. What things do we need to make electrolysis?

12. What is the function of electric current during electrolysis?

13. What energy is necessary to start a chemical reaction?

14. Do the properties of products remain identical as those of reactants during a chemical reaction?

15. What chemical reactions happen all around us?

16. What colour does a solution usually have?

17. Are the solid particles bigger than those of a solution?

18. What atom elements is water made up of?

19. How is water surface formed?

20. What things can water «wet»?

4. Translate and make a plan of the text «What are organic compounds» (Additional Reading).