Answer the following questions.
Date: 2015-10-07; view: 654.
Identify the stressed sound in each word as in the example. Practise reading.
READING
Physicists, discovery, X-rays, photograph, through, mysterious, opaque, phenomenon, self-satisfaction, uranium salts, pure, honour, enough, conclusion, tons, possess, electrify, phosphorescent, triumphant, minute, hydrogen, weight, structure.
7. Practise reading the following numerals:
2500, 1869, 1895, 1898, the 21st century, 1932, 3,000,000, 235, 125,000,000th
8. Read the text "The dawn of atomic physics" and put the sentences into chronological order.
| A | Marie and Pierre were especially interested in learning more about pitchblende. | |
| B | After that Marie and Pierre isolated a second new element. | |
| C | The discovery of W.K. Roentgen showed that the work of physicists was far from being at the end. | |
| D | To answer this question, they purified huge amounts of the natural ore. | |
| E | They chose the name "radium" because the element gives off such intense radiation. | |
| F | Eventually, they isolated a new element that gave off radiation much more intensely than did the pitchblende itself. | |
| G | Becquerel's discovery caused great excitement among scientists. | |
| H | What was in the ore that was giving off radiation, they asked. | |
| I | The Curies named the new element polonium. | |
| J | Marie Curie found out that the salt of thorium gave off mysterios rays. |
1. 
What opinion did scientists have as for the development of physics at the end of the 19th century?
2. What discovery was announced in 1895?
3. What is a mysterious ray which penetrates opaque objects called?
4. Who made the discovery of the rays given off by uranium salts?
5. Which of the two, pitchblende or pure uranium, gave off rays four times stronger?
6. What new element did the Curies obtain in 1898?
7. What properties did this new substance possess?
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