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（8分）已知五种短周期元素在周期表中的相对位置如下表所示。

A     
     B
c d  e
（1）上述元素中离子半径最大的是_______________（填写元素符号）。

（2）已知A、B、C、D、E五种化合物均由上述元素中的几种组成。它们之间的转换关系如图所示，且A、B、E三种物质含有相同的一种金属元素，C和D分别是常见的强酸和强碱，则：①A、B、E所含的该金属元素的原子结构示意图为_________________________________________；

②若将D逐滴滴入A的溶液中至过量，反应过程中的离子方程式依次为______________________________________________________________。

答案

（1）S（2分）

（2）①（2分）

②Al3++3OH—=Al（OH）3↓；Al（OH）3+OH—=［Al（OH）4］—（每个方程式2分，共4分）

选择题

对于某一化学事实，下列表述错误的是（　　）

A．在加入铝粉能放出氢气的溶液中K+、NH4+、CO32-、C1-可能大量共存

B．向Fe（OH）3胶体中逐滴滴入过量的稀硫酸，能发生“先沉淀后溶解”现象

C．向饱和碳酸钠溶液中通入过量CO2的离子方程式为：2Na++CO32-+CO2+H2O═2NaHCO3↓

D．0.1mol•L-1乙酸溶液的pH约为3，可证明它是弱电解质
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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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