Read the text about hydrogen as the source of energy and think about the following questions.
1. Where can we use hydrogen?
2. How does hydrogen move to the carburetor?
3. What will happen with hydrogen in a road accident?
4. Is it necessary to use hydrogen as a fuel?
Specialists consider hydrogen an extremely promising energy source. The reserves of hydrogen are practically unlimited. Per unit of weight, it contains almost three times more thermal energy than benzene. Another plus is that hydrogen can be used as fuel in transport, industry and the home.
Extensive use of hydrogen as an energy source will help keep the environment clean Ц hydrogen combustion produces simply the vapour of distilled water.
The experiment has been conducted with the serial minibus RAF-2203. Its storage compartment holds two cryogenic vessels containing 5or 6 kilograms of liquid hydrogen. From these vessels it is pumped at a pressure of 1.5 atmospheres into a special reservoirs, where it is transformed into gaseous hydrogen that is then piped into the carburator.
Trials have shown that adding five to ten per cent hydrogen to benzene results in considerably greater combustion of benzene and increases engine efficiency by 40-45 per cent. Besides, the toxicity of the exhaust falls to one hundredth of prior exhaust, since the carbonic oxide content becomes smaller.
To determine the consequences of what might happen to cryogenic reservoirs in a road accident, liquid hydrogen was spilled onto the ground. The hydrogen instantaneously evaporated, and the vapour dissipated so quickly that no combustion was possible. So even in an emergency there was no possibility of an explosion or fuel combustion. And as everyone is aware, when a conventional tank with fuel is damaged, the spilt fuel is liable to burn.
Hydrogen opens up new prospects in metallurgy. It is not only the source of high temperatures, but also a substance which can replace coal and coke in iron reduction technology. In this process, harmful gases ejected by metallurgical factories are eliminated.
Decide if the statements are true, false or there is no evidence.
1. Using hydrogen as fuel in cars doesnТt affect environment.
2. The addition of hydrogen to benzene doesnТt increase the process of combustion.
3. The explosion is possible as a result of accident when fuel is benzene.
4. Harmful gases are eliminated when we use coal metallurgy.
5. Spilt fuel can burn.
Choose the sentence fragment that best completes each of the following.
1. The reserves of hydrogen Е
a) can be counted.
b) are enormous.
c) are unlimited.
2. The use of hydrogen as a source of energy Е
a) will be useful for environment.
b) will save our metallurgical factories.
c) will increase the toxicity of the exhaust.
3. Tests showed Е
a) good results of using benzene with hydrogen.
b) that carbonic oxide content increases.
d) that hydrogen evaporated.
4. Liquid hydrogen in an emergency Е
a) is able to burn.
c) is explosive.
Translate sentences paying attention to the infinitive and infinitive constructions.
1. Oil is known to be one of the most important sources of energy.
2. Petroleum is believed to have been formed from decaying vegetable and animal remains.
3. Drilling is considered to be the principal exploration method and it is widely used when deposits are of large dimensions.
4. Until recently a depth of 50-ft overburden was considered to be the maximum.
5. Coal is still the most important fuel and is likely to remain the main source of energy for years to come.
6. The computerized systems of planning and control proved to be reliable.
7. The geological investigations to be carried out include field prospecting and exploration.
8. The possibility of making direct observations in working depends on the mining system to be applied.
9. The work of geologists at mines has its own specific character and a range of problems to be solved during the exploitation of the deposit.