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问题 填空题

按要求从甲烷、水、氧化铁、硫酸铜、氢氧化铁、氢氧化钡六种物质中选择合适的物质，将其化学式填写在下列空格中．

（1）一种最简单的有机物：______（2）一种金属氧化物：______

（3）一种难溶的碱：______（4）一种可溶的盐：______．

答案

（1）根据已有的知识进行分析，甲烷是最简单的有机物，其化学式为：CH4．

（2）含有金属元素的氧化物属于金属氧化物，氧化铁属于金属氧化物，其化学为：Fe2O3．

（3）碱是指在电离时产生的阴离子全部是氢氧根离子的化合物，氢氧化铁是难溶于水的碱，其化学式为：Fe（OH）3．

（4）盐是由金属离子和酸根离子组成的化合物，硫酸铜是可溶性的盐，其化学式为：CuSO4．

故答案为：（1）CH4；（2）Fe2O3；（3）Fe（OH）3；（4）CuSO4．

单项选择题

气管切开时，易引起无名动脉损伤的位置低于

A．2气管软骨环

B．1气管软骨环

C．5气管软骨环

D．4气管软骨环

E．3气管软骨环
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填空题

Motivation is "the driving force within individuals that impels them to action." And goals are the sought-after results_____(1) motivated behavior.Motivation can be either positive or negative_____(2) direction. We may feel a driving force toward some object or condition, _____(3) a driving force away from some object or condition. For example, a person may be impelled toward a restaurant to fulfill a need, hunger, and away_____(4) an airplane to fulfill a need of safety. Some psychologists refer to positive drives_____(5) needs, wants or desires,_____(6) negative drives as fears or aversions._____ (7), though negative and positive motivational forces seem to differ dramatically_____(8) terms of physical and sometimes emotional activity, they are basically similar in_____(9) they both serve to initiate and sustain human behavior.____(10) this reason, researchers often refer _____(11) both kinds of drives or motives as needs, wants and desires.Goals, _____(12), can be either positive or negative. A positive goal is one toward_____ (13) behavior is directed and it is often referred to as an approach object. A negative goal is _____(14) from which behavior is directed away and it is sometimes referred to as an avoidance object. Since both approach and avoidance goals can be considered objectives of motivated behavior, most researchers refer to_____(15) types simply as goals. Consider this example. A middle-aged woman may wish to remain_____(16) attractive as possible. Her positive goal is to appear desirable, and_____(17) she may use a perfume advertised to make her irresistible. A negative goal may be to prevent her skin_____(18) aging, and therefore she may buy and use face creams._____(19) the former case, she uses perfume to help her achieve her positive goal — attractiveness; in the____(20) case, she uses face creams to help avoid a negative goal — wrinkled skin.
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