HYDROGEN
1. Hydrogen is the most abundant element in the universe, making up 75% of normal matter by mass and over 90% by number of atoms.
2. Hydrogen gas, H2, was first artificially produced and formally described by Paracelsus, 1493 – 1541. 3. While mixing metals with strong acids he was unaware that the flammable gas produced by this chemical reaction was a new chemical element. 4. In 1671 Robert Boyle rediscovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. 5. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by identifying the gas from a metal-acid reaction as "inflammable air" and further finding that the gas produces water when burned. 6. Cavendish had stumbled on hydrogen when experimenting with acids and mercury. 7. He was even able to accurately describe several key properties of hydrogen. 8. In 1783, Antoine Lavoisier gave the element the name of hydrogen when he reproduced Cavendish´s finding that water is produced when hydrogen is burned. 9. Lavoisier´s name for the gas remained.
10. Throughout the universe, hydrogen is mostly found in great abundance in the existing stars and gas giant planets. 11. Molecular clouds of hydrogen are associated with star formation. 12. Under ordinary conditions on Earth, elemental hydrogen occurs as the diatomic gas. . 13 However, hydrogen gas is very rare in the Earth´s atmosphere because of its light weight, which enables it to escape from Earth´s gravity more easily than heavier gases.
14. Elemental hydrogen is relatively rare on Earth, and is industrially produced from hydrocarbons such as methane. 15. Hydrogen may be produced from water using the process of electrolysis, but this process is presently significantly more expensive commercially than hydrogen production from natural gas.
16. The next most important point to be noted is the application of hydrogen. 17. It is in great demand in the automotive, chemical, power generation, aerospace, and telecommunications industries. 18. Hydrogen is used as a hydrogenating agent, particularly in increasing the level of saturation of unsaturated fats and oils , and in the production of methanol. 19 It is similarly the source of hydrogen in the manufacture of hydrochloric acid. 20. Hydrogen is also used as a reducing agent of metallic ores.
21. Most of the Earth´s hydrogen is in the form of chemical compounds such as hydrocarbons and water. 22. Hydrogen gas is produced by some bacteria and algae and is a natural component of air.

Пояснение к тексту
аlgae – морская водоросль

II. Расставьте пункты плана согласно логике текста:
1. The usage of hydrogen.
2. Hydrogen in nature.
3. The production of hydrogen.
4. The history of hydrogen study.
5. Where can hydrogen be found in the Earth?

III. Выпишите из текста предложения, содержащие инфинитив и
предложения с причастием 1, укажите их функции. Предложения
переведите.

IV. Перепишите предложения; подчеркните глагол-сказуемое и определите его видовременную форму и залог; напишите форму инфинитива. Предложения переведите. (См. образец 3).
1. The new drug is being tested in the laboratory.
2. The scientist was completely interested in the practical application of his discoveries.
3. Students are carrying out their laboratory tests in modern laboratories for two weeks.

V. Перепишите предложения, подчеркните глагол «to do» и определите является ли он смысловым, вспомогательным или словом заместителем.
Предложения переведите.
1. We produced the necessary compound earlier than they did.
2. The properties of this substance do not make it possible to use it in this experiment.
3. The students did all the best to pass examinations well.