Answer the following questions:
ВАРИАНТ 1
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Hydrocarbons
Hydrocarbons are compounds of hydrogen and carbon that at normal temperatures and pressures may be gaseous, liquid or solid depending on the relative proportion of the various hydrocarbons present in the mixture. In its widest sense “petroleum” embraces all hydrocarbons occurring naturally in the earth. In its narrower, commercial sense, “petroleum” usually includes liquid deposits – crude oil, the gaseous ones being known as “natural gas” and the solid ones as “bitumen”, “asphalt” or “wax” according to their composition. Most crude oils, although liquid as such, contain gaseous and solid hydrocarbons in solution. The gases are known to come out of solution either on the release of pressure as the crude oil is produced or during the first stages of refining, and contribute to the total natural gas production. Some of the solids are recovered during refining as bitumen and wax, some remain in solution in the liquid oil produce. Natural gas is also found associated with crude oil as “gas cap” above the oil or unassociated with oil. Crude oil and natural gas are the raw materials of the petroleum industry. It is the business of the industry to find them, to produce them from the ground, to process them and to manufacture technically useful products from them. Is should be also stressed that the word’s demand for oil continues to grow and had doubled by 1990 and it comes to 80,2 m.b/d. Thus, for a century and a half the industry has grown into one of the most important in the world, remarkable for its size, complexity and geographical extent.
Answer the following questions:
1.What are hydrocarbons?
2.What states may hydrocarbons be in?
3.What are the raw materials of the petroleum industry?
4. What are the functions of the petroleum industry?
Choose the right statement
1. a) Hydrocarbons are solely liquid mixtures.
b) Hydrocarbons may be gaseous, liquid and solid.
c) Hydrocarbons may be liquid and solid.
2. Liquid hydrocarbons are usually referred to as:
a) “condensate”; b) gas cap; c) petroleum.
3. a) Gases are known to enter petroleum in underground reservoirs;
b) Gases are known to come out of solution during oil production and refining;
c) Gases are known to remain in underground reservoir during oil production.
4. a) All solid compounds are recovered during refining.
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b) Only solid compounds are recovered during refining.
c) Some of the solids are recovered during refining.
4. Make up 5 types of questions to these sentences:
1. Hydrocarbons are compounds of hydrogen and carbon
2. Most crude oils contain gaseous and solid hydrocarbons in solution.
ВАРИАНТ 2
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A Catalyst
A catalyst is a substance that alters the speed of a chemical reaction without itself undergoing any chemical change, usually only a small quantity of it is required. Catalysts arc usually specific in action; thus, a catalyst for one reaction is more often than not useless for any other reaction. They are extremely important substances not only in the laboratory but also in chemical industry and in biological systems. Thus, the manufacture of sulphuric acid, ammonia and margarine involves the application of catalysts, the most of the chemical reactions that occur in our bodies arc regulated by these substances. In biological systems substances called enzymes function as catalysts, c. g., specific enzymes arc used to aid the digestion of food in the stomach. Chemists have discovered the great majority of reactions that proceed without catalysts. But there are almost innumerable other reactions that cannot be practically effected without a catalyst. The phenomenon in which a relatively small amount of a foreign material, called a catalyst, augments the rate of a chemical reaction is called catalysis. A catalyst provides the possibility of new elementary processes taking place, but it is not consumed during the reaction. If we cannot have it regenerated, there is no catalysis.
Answer the following questions:
1.What is the catalyst?
2.What is the function of the catalyst?
3.Where is this substance used?
4.What does a catalyst provide?
Choose the right statement
1. а) A catalyst is an element that alters the speed of a chemical reaction
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b) A catalyst is a substance that alters the speed of a chemical reaction
c) A catalyst is an element that alters the quality of a chemical reaction
d) A catalyst is a substance that doesn't alter the quality of a chemical reaction
2. a) Catalysts are important substances in chemical industry.
b) Catalysts are important only in chemical industry.
c) Catalysts aren't important substances in chemical industry.
d) Materials are important substances in chemical industry.
3. a) There are few reactions that proceed without catalysts.
b) Chemists have discovered the great majority of reactions that proceed with catalysts.
c) No reaction can proceed without a catalyst.
d) Chemists have discovered the great majority of reactions that proceed without catalysts.
4. а) A catalyst undergoes little changes in the reaction.
b) A catalyst undergoes large changes in the substance.
c) A catalysis undergoes large changes in the reaction.
d) A catalyst undergoes large changes in the reaction.
4. Make up 5 types of questions to these sentences:
1. Catalysts are important substances in the laboratory and in chemical industry.
2. The manufacture of sulphuric acid involves the application of catalysts
ВАРИАНТ 3
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The refining process
Crude oil is not very useful in the form it comes in out of the ground as it contains hundreds of different types of hydrocarbons all mixed together. It is necessary to separate the different types of hydrocarbons to have anything useful, and this process is called “oil refining”. An oil refinery is an industrial process plant where crude oil is processed and refined into useful petroleum products, such as gasoline and diesel fuel. The oil refining process starts with a fractional distillation column. The various components of crude oil have different sizes, weights and boiling temperatures. The first step is to separate these components (called fractions). Because they have different boiling temperatures, they can be separated easily by a process called fractional distillation. It is the oldest and most common way in the refining process. You basically heat crude oil up, let it vaporize and then condense the vapor. Heating is usually done with high pressure steam to temperatures of about 1112 degrees Fahrenheit / 600 degrees Celsius. The mixture boils, forming vapor (gases); most substances go into the vapor phase. The vapor enters the bottom of a long column (fractional distillation column) that is filled with trays or plates. The trays have many holes or bubble caps in them to allow the vapor to pass through. The trays increase the contact time between the vapor and the liquids in the column. The trays help to collect liquids that form at various heights in the column. There is a temperature difference across the column (hot at the bottom, cool at the top). The vapor rises in the column. As the vapor rises through the trays in the column, it cools. When a substance in the vapor reaches the height where the temperature of the column is equal to that substance's boiling point, it will condense to form a liquid. (The substance with the lowest boiling point will condense at the highest point in the column; substances with higher boiling points will condense lower in the column.). The trays collect the various liquid fractions. The collected liquid fractions may pass to condensers, which cool them further, and then go to storage tanks or go to other areas for further chemical processing.
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