Petroleum products, such as gasoline, kerosene, home heating oil, residual fuel oil, and lubricating oils, come from one source crude oil found below the earths surface, as well as under large bodies of water, from a few hundred feet below the surface to as deep as 25,000 feet into the earths interior. Sometimes crude oil is secured by drilling a hole through the earth, but more dry holes are drilled than those producing oil. Pressure at the source or pumping forces crude oil to the surface.
Crude oil wells flow at varying rates, from ten to thousands of barrels per hour. Petroleum products are always measured in 42-gallon barrels.
Petroleum products vary greatly in physical appearance: thin, thick, transparent or opaque, but their chemical composition is made up of only two elements; carbon and hydrogen, which form compounds called hydrocarbons. Other chemical elements found in union with the hydrocarbons are few and are classified as impurities. Trace elements are also found, but these are of such minute quantities that they are disregarded. The combination of carbon and hydrogen forms many thousands of compounds which are possible because of the various positions and joinings of these two atoms in the hydrocarbon molecule.
The various petroleum products are refined from the crude oil by heating and condensing the vapors. These products are the so-called light oils, such as gasoline, kerosene, and distillate oil. The residue remaining after the light oils are distilled is known as heavy or residual fuel oil and is used mostly for burning under boilers. Additional complicated refining processes rearrange the chemical structure of the hydrocarbons to produce other products, some of which are used to upgrade and increase the octane rating of various types of gasolines.
26. Which of the following is NOT TRUE?
A. Crude oil is found below land and water.
B. Crude oil is always found a few hundred feet below the surface.
C. Pumping and pressure force crude oil to the surface.
D. A variety of petroleum products is obtained from crude oil.
27. Many thousands of hydrocarbon compounds are possible because_______.
A. the petroleum products vary greatly in physical appearance
B. complicated refining processes rearrange the chemical structure
C. the two atoms in the molecule assume many positions
D. the pressure needed to force it to the surface causes molecular transformation
28. Which of the following is TRUE?
A. The various petroleum products are produced by filtration.
B. Heating and condensation produce the various products.
C. Chemical separation is used to produce the various products.
D. Mechanical means such as the centrifuge are used to produce the various products.
29. Crude oil is brought to the surface by_______.
A. expansion of the hydrocarbons
B. pressure and pumping
C. vacuum created in the drilling pipe
D. expansion and contraction of the earths surface
30. Which of the following is not listed as a light oil?
A. distillate oil B. gasoline
C. lubricating oil D. kerosene
26. B 27. C 28. B 29. B 30. C
我心中的美景
月亮的自我介绍
全球十大最受欢迎旅游城市
国际英语资讯:S. African president announces 500-bln-rand COVID-19 plan
月球奥秘知多少?
麦凯恩乌克兰“示威” 为反对派助阵
国内英语资讯:Spotlight: Chinas economy expected to recover in Q2 amid COVID-19: experts
大公司不一定是好的投资之选
我爱我家
女外交官在美被捕激怒印度 美国务卿出面表“遗憾”
美国安全局“肌肉发达” 被指“行窃”谷歌雅虎
我爱我家
No Sell, No Kill 没有买卖就没有伤害
国内英语资讯:Xi Focus-Quotable Quotes: Xi Jinping on poverty alleviation
来自月球的回望
月亮照着你月亮照着我
国际英语资讯:Trump, British PM Johnson reaffirm cooperation to reopen global economies
体坛英语资讯:Chebet, Chemonges seek fast times at Lake Biwa Marathon in Japan
探索月球奥秘
乔治小王子成威廉夫妇出访焦点
未来月球
探索月球奥秘的作文
探索月球奥秘
人社部:打出政策组合拳,减负援企稳岗位
月亮月亮我问你
国际英语资讯:European nations ease lockdowns with caution
新冠隔离期间睡不好?许多人说噩梦变多了
我家的一件珍品
我在月球上的一天
时间银行
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |