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问题 选择题

小明用“三”对初中所学化学知识进行了归纳总结，其中正确的是

A．大气污染产生的环境问题有“三种”：温室效应、臭氧层破坏、水体富营养化

B．不显电性的微粒有“三种”：质子、中子、电子

C．一般燃烧必须同时满足“三点”：可燃物、与氧气或空气接触、温度达到着火点

D．过滤操作用到的仪器只有“三种”：漏斗、烧杯、铁架台

答案

答案：C

题目分析：大气污染产生的环境问题不包含水体富营养化；质子和电子带电，中子不带电；一般燃烧必须同时满足“三点”：可燃物、与氧气或空气接触、温度达到着火点；过滤操作用到的仪器有漏斗、烧杯、铁架台和玻璃棒。选C。

点评：识记内容，难度不大，原子由原子核和核外电子构成，原子核由质子和中子构成，原子中，质子数=核电荷数=核外电子数=原子序数。

填空题

Tragedies have a way of making people rethink their (1) and find a new focus. They make people think about what a society needs in order to (2) . The notion of doing something to take control of society or of our fate as humans might be dated back to ancient times of the (3) . Now, in the early 21st century, " social (4) " are trying to take back some (5) over society’s direction once again. A social inventor is not necessarily a social (6) , a social (7) or someone who works in a (8) industry or invents new (9) and consumer products. A social inventor is using the power of (10) thinking, to come up with ideas for (11) in certain communities or sections of society. They have a vision of a (12) world and create new systems or practices. Their ideas may seem (13) or impossible. They are usually quite (14) people. But some of these creative thinkers have (15) and quietly changed the way we live. Social inventions do not have to be (16) . Sometimes they are new (17) for neighborhoods or communities, or even very (18) ideas. The idea of social inventions has become so popular in recent years. It shows how much people desire to make a (19) in our society and not remain (20) .

Tragedies have a way of making people rethink their (1) and find a new focus. They make people think about what a society needs in order to (2) . The notion of doing something to take control of society or of our fate as humans might be dated back to ancient times of the (3) . Now, in the early 21st century, " social (4) " are trying to take back some (5) over society’s direction once again. A social inventor is not necessarily a social (6) , a social (7) or someone who works in a (8) industry or invents new (9) and consumer products. A social inventor is using the power of (10) thinking, to come up with ideas for (11) in certain communities or sections of society. They have a vision of a (12) world and create new systems or practices. Their ideas may seem (13) or impossible. They are usually quite (14) people. But some of these creative thinkers have (15) and quietly changed the way we live. Social inventions do not have to be (16) . Sometimes they are new (17) for neighborhoods or communities, or even very (18) ideas. The idea of social inventions has become so popular in recent years. It shows how much people desire to make a (19) in our society and not remain (20) .
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单项选择题

项目技术体系中，特大型项目技术部应按要求设置专业工程师（）人以上。

A.3

B.4

C.5

D.6
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