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问题 选择题

下列溶液中，Na+ 数目最多的是(   )

A．1mol/L Na2SO4溶液200mL

B．0.9mol/L Na3PO4溶液200mL

C．2.5mol/L NaOH 溶液100mL

D．1mol/L NaHCO3溶液300mL

答案

答案：B

题目分析：1mol/L Na2SO4溶液200mL，n(Na+)为0.4mol；0.9mol/L Na3PO4溶液200mL ，n(Na+)为0.54mol；2.5mol/L NaOH 溶液100mL，n(Na+)为0.25mol；1mol/L NaHCO3溶液300mL，n(Na+)为0.3mol。所以B项中Na+的数目最多。答案选B。

考点；物质的量计算

点评：本题根据n=cV来计算。

填空题

2011年11月3日，神舟八号与天宫一号完美“牵手”，成功实现交会对接（如下图）。

(1) 对接后，以“神舟八号”为参照物，则“天宫一号”是_____的（选填“运动”或“静止”）；

(2) 天宫一号的舱外安装有摄像头，它清晰的拍摄了飞船的对接过程，摄像机的镜头相当于__  __透镜，拍摄时神舟八号飞船离摄像机镜头的距离（物距）与焦距的关系是：                 。
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单项选择题

Attempts to understand the relationship between social behavior and health have their origin in history. Dubos (1969) suggested that primitive humans were closer to the animals (1) they, too, relied’upon their instincts to stay healthy. Yet some primitive humans (2) a cause and effect relationship between doing certain things and alleviating (3) of a disease or (4) the condition of a wound. (5) there was so much that primitive humans did not (6) the functioning of the body, magic became an integral component ofthe beliefs about the causes and cures of heath (7) Therefore it is not (8) that early humans thought that illness was caused (9) evil spirit. Primitive medicines made from vegetables or animals were invariably used in combination with some form of ritual to (10) harmful spirit from a diseased body.

One of the. earliest (11) in the Western world to formulate principles of health care based upon rational thought and (12) of supernatural phenomena is found in the work of the Greek physician Hippocrates. The writing (13) to him has provided a number of principles underiying modern medical practice. One of his most famous (14) , the Hippocratic Oath, is the foundation of contemporary medical ethics.

Hippocrates also argued that medical knowledge should be derived from a (15) of the natural science and the logic of cause and effect relationships. In this (16) thesis, On Air, Water, and Places, Hippocrates pointed out that human well-being is (17) by the totality of environmental (18) : living habits or lifestyle, climate, geography of the land, and the quality of air, and food. (19) enough, concerns about our health and the quality of air, water, and places are (20) very much written in twentieth century.

11（）

A.expedition

B.incentives

C.stimuli

D.endeavors
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