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English for students of Chemistry (1).docx
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X. Match the words (word combinations) in column a with their definitions in column b.

A

B

1. chemistry

a) a substance that can be decomposed into two or more substances

2. concept

b) different parts of which something is made up

3. density

c) size or quantity taken as measurement of the space filled by matter

4. substance

d) the study of substances – their structure, properties and reactions

5. compound

e) process of converting substances into other substances

6. chemical reaction

f) a general idea or principle

7. volume

g) the relationship of the amount of matter in something to the space into which the matter is packed

8. composition

h) a homogeneous species of matter with definite chemical composition

XI. Answer the questions on the text.

1. What is the origin of chemistry?

2. Who’s discoveries did modern chemistry begin with?

3. What does chemistry deal with?

4. What is a chemical change? What is a physical change?

5. What do all forms of matter consist of?

6. What are the building blocks of matter?

7. What is a compound?

8. What do the terms analysis and synthesis mean?

9. What are the three states of matter? Speak about the peculiarities of matter in

each of the states.

10. How are the transformations of matter from one state into another called?

11. What are the chemical properties of matter?

12. What are the physical properties of matter?

13. Why is the role of chemistry in the modern world so great?

XII. Read and translate the text using the dictionary, discuss the chemical phenomenon described. Give your own example of a chemical change.

WHAT IS THE CHEMICAL CHANGE?

What is the chemical change? Let’s set up an apparatus with two test-tubes. In one of them there is a red powder which chemists call mercury oxide. We fill the other tube with water. When we heat the mercury oxide the bubbles of gas go up in this test-tube, and we can see little drops of silvery material gathering on the side of the tube with the red powder. This material is mercury. The second tube with the water now contains oxygen.

What has taken place in this experiment? We have broken up one substance into two. Mercury oxide is a compound. By means of heating we have separated the atoms of mercury and oxygen, and two substances different from the red oxide have appeared. These two substances are different from the original substance. They are also different from each other. Chemists called this type of transformation a chemical change.

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