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Before reading the text below complete the sentences 1-3




CONTENTS

Section 1 ATOMIC NATURE OF MATTER

Section 2 NUCLIDES

Section 3 MASS DEFECT

Section 4 BINDING ENERGY

Section 5 MODES OF RADIOACTIVE DECAY

Section 6 RADIOACTIVITY

Section 7 NEUTRON INTERACTIONS

Appendix 1 Mathematical Signs, Symbols and Abbreviations

Appendix 2 Greek Alphabet

Appendix 3 Units and Dimensions

Appendix 4 Report and Presentation

 

REFERENCES

 

SECTION 1

ATOMIC NATURE OF MATTER

LEAD-IN

Study this list of points to consider when deciding whether to study engineering. Tick [√] the statements which refer to you. Then ask your partner which statements refer to him or her.

1 You enjoy practical projects - creating and investigating things.

2 You like finding out how things work.

3 You are interested in improving the environment.

4 You like helping people.

5 You enjoy solving problems.

6 You enjoy organizing activities.

7 You enjoy science programmes on TV or on the radio.

 

If you have ticked most of these statements, engineering is the right course of study for you.

 

Read the following text and do the tasks below (1-3):

In 1661 the English chemist Robert Boyle published the modern criterion for an element. He defined an element to be a basic substance that cannot be broken down into any simpler substance after it is isolated from a compound, but can be combined with other elements to form compounds. To date, 105 different elements have been confirmed to exist, and researchers claim to have discovered three additional elements. Of the 105 confirmed elements, 90 exist in nature and 15 are man-made.

Another basic concept of matter that the Greeks debated was whether matter was continuous or.discrete. That is, whether matter could be continuously divided and subdivided into ever smaller particles or whether eventually an indivisible particle would be encountered. Democritus in about 450 B.C. argued that substances were „ultimately composed of small, indivisible particles that he labeled atoms. He further suggested that different substances were composed of different atoms or combinations of atoms, and that one substance could be converted into another by rearranging the atoms. It was impossible to conclusively prove or disprove this proposal for more than 2000 years.

The modern proof for the atomic nature of matter was first proposed by the English chemist John Dalton in 1803. Dalton stated that each chemical element possesses a particular kind of atom, and any quantity of the element is made up of identical atoms of this kind. What distinguishes one element from another element is the kind of atom of which it consists, and the basic physical difference between kinds of atoms is their weight.

 

Complete the following sentences using the information from the text and your knowledge.

1. The English chemist Robert Boyle …

2. The Greeks debated …

3. Democritus argued …

4. The English scientist John Dalton proposed …

 

Work in pairs. Decide whether the statements below (1-3) are true or false. Correct the false sentences. Share your ideas with other students in your group.

1. Robert Boyle argued that an element can be broken down into any simpler substance after it is isolated from a compound.

2. It was impossible to finally prove or disprove the Democritus suggestion that different substances were composed of different atoms or combinations of atoms, and that one substance could be converted into another by rearranging the atoms.

3. Robert Boyle was the first to prove the atomic nature of matter.

 

3. Using information from the text say a few words about:

1. the modern criterion for an element published by Robert Boyle

2. continuous or.discrete matter

3. Democritus proposal that was impossible to conclusively prove or disprove this proposal for more than 2000 years

4. the modern proof for the atomic nature of matter proposed by John Dalton in 1803

READING

TEXT 1

Before reading the text below complete the sentences 1-3.

1. Subatomic particles are …

2. Gravity, electromagnetism, strong nuclear force and weak nuclear force are …

3. A gauge boson is …

 

1.2. You are going to read a text about subatomic particle theory. Six phrases have been removed from the text. Choose from the sentence A – G the one which fits each gap (1 – 6). There is one extra phrase, which you don’t need to use.

A which governs the aggregation of matter

B that emerges when a neutron changes by beta decay into a proton

C that is independent of charge

D which transmits the electromagnetic force between electrically charged objects

E that provide this mortar are associated with four basic forces

F which acts only between quarks

G which incorporates all four fundamental forces





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