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【简答题】
下列短文中加有下划线的词语，可能指“反应条件”“实验现象”或“实验结果”。试从这三者中选择合适的内容分别填入括号内。 加热碱式碳酸铜（ ）， 绿色粉末变成黑色（ ）， 管壁出现小液滴（ ），同时 产生能使澄清石灰水变浑浊的气体（ ）， 生成了氧化铜、水、二氧化碳（ ）。
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参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】催化二氧化碳和氨合成氨甲酰磷酸反应的酶及分布是（ ）。
A.
氨甲酰磷酸合成酶I，细胞液
B.
氨甲酰磷酸合成酶I，线粒体
C.
氨甲酰磷酸合成酶Ⅱ，细胞液
D.
氨甲酰磷酸合成酶Ⅱ，线粒体
【单选题】It’s generally agreed that the greatest threat facing the world today is the warming of the earth’s atmosphere, commonly called global warming or the greenhouse effect. But what is the cause of the gr...
A.
It’s generally agreed that the greatest threat facing the world today is the warming of the earth’s atmosphere, commonly called global warming or the greenhouse effect. But what is the cause of the greenhouse effect
B.
We have been producing too many of the gases which, when they are released into the earth’s atmosphere, trap heat, and thus raise their temperatures. There are several gases involved, but the main ones are carbon dioxide (二氧化碳) and chlorofluorocarbons (氯氟甲烷)--often called CFCs. The carbon dioxide comes from burning forests and from bunting fossil fuels such as oil and coal. The CFCs are given off by refrigerators and air-conditioning systems. Carbon dioxide is to blame for 56% of the greenhouse effect, and CFCs for 23%.
C.
The global warming we are experiencing now is only a result of the carbon dioxide and other gases we have dumped into the atmosphere up to the 1960s. In other words, the damage may have already been done. Temperatures are expected to increase by at least 1.3 Celsius degrees by 2030 and 3 degrees by the year 2070.
【单选题】At the first sight the planet Mars does not appear very welcome to any kind of life．It has very little oxygen and water; the temperature at night is below -50℃ and winds of 100 miles per hour cause se...
A.
there is no life there now
B.
there is a large amount of water at the poles
C.
the Mars may be able to support life in the future
D.
conditions may have been similar to those on the Earth