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某学校修操场拉来许多生石灰，实验员为来年做实验，用塑料袋装了一大块放到实验室的柜橱里，但来年用的时候发现，本来坚硬的生石灰已经列成许多小块，塑料袋也被撑破了．

（1）生石灰变碎的原因是（用化学方程式表示）．

（2）对变碎的白色固体中是否含有碳酸钙小红和小童有不同的看法，于是他们设计了实验：取一钥匙白色固体（约3g）加入试管中，加入约20mL水，充分震荡，试管底部有固体剩余，他们得出结论：白色固体中含碳酸钙．

结合上图，指出他们实验的错误之处在于______．

（3）请你设计实验鉴定白色固体中含有碳酸钙．

步  骤现  象结  论
取少量白色固体于试管中．

______．

______白色固体中含有碳酸钙．
（4）由此我们知道，生石灰保存必须注意______．

答案

（1）生石灰的成分为氧化钙，可与水反应生成氢氧化钙，生成的氢氧化钙容易和空气中的二氧化碳反应生成碳酸钙，方程式为：CaO+H2O═Ca（OH）2，Ca（OH）2+CO2═CaCO3↓+H2O；

（2）根据图示信息可知：固体溶于水会放大量的热，而随温度的升高，氢氧化钙的溶解度逐渐减小，一定条件下，可能会析出氢氧化钙固体，不一定是碳酸钙固体；

（3）碳酸钙的检验方法：向固体中加入稀盐酸，会产生使石灰水变浑浊的气体二氧化碳；

（4）根据氧化钙易和水、二氧化碳等物质反应，所以生石灰保存时必须注意要密封保存．

故答案为：（1）CaO+H2O═Ca（OH）2，Ca（OH）2+CO2═CaCO3↓+H2O；

（2）固体溶于水放大量的热，随温度的升高，氢氧化钙的溶解度逐渐减小，一定条件下，可能会析出氢氧化钙固体；

（3）向固体中加稀盐酸、产生使石灰水变浑浊的气体；

（4）要密封保存．

单项选择题

剔除由不良元器件，零部件或工艺缺陷引起的早期故障的方法是( )。

A．环境应力筛选试验

B．常规的方法

C．目视检查

D．任何方法或试验
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问答题

(46)Within the modern study of religion the division between philosophy of reli- gion and the histolw of religions-long regarded as a truism insofar as it reflects the distinction between universal and particular-has become increasingly blurred in recent years with the growing influence of’ cultural and critical theory on the humanities and social sciences. Unlike the earaier paradigmatic split between theology and anthropology (or social science methodology) , cultural theory has helped not only to dismantle well worn dualisms such as religion/politics, theism/atheism, sacred/secular, but more importantly has helped to narrow the gap between academic practices and cultural practices such as religion that scholars seek to study. (47)That is to say, cultural theory has simultaneously problematized and challenged essentialist and theological tendencies (such as dreams of absolute principles, supernatural origins, ahistorical authorities, pure traditions etc. ) as well as scholars’ claims to methodological objectivity and impartiality, since the academy far from being a site of neutral value-free analysis, is itself thoroughly implicated in cultural realities. Indeed in what might seen as a reversal of critical theory’s atheistic roots in the "masters of suspicion" contemporary cultural theory has been adapted by scholars not only to successfully dispute the atheistic presuppositions of modern secular thinking in the social sciences, thereby revitalizing religious and theological reflection in the Christian and Judaic traditions, but, more surprisingly perhaps, it has legitimized the use of phenomena from these particular traditions as resources for critical thinking about religion per se.

(48) By contrast, however, the effects of critical theory on the study of nonWestern religions has not only been far more modest, in many cases it seems also to have had precisely the opposite effect. In the study of South Asian religions, for example, the effect of critical theory seems to have reinforced the priority of the secular. In his recent work "Provincialising Europe" Dipesh Chakrabarty points out the very different interventions of critical theory in the two traditions. (49) Whereas in the Western intellectual traditions fundamental thinkers who are long dead and gone are treated not only as people belonging to their own times but also as though they were our contemporaries, the thinkers and traditions of South Asia, once unbroken and alive in their native languages, are now matters of historical research. These traditions are treated as truly dead, as history. Few if any social scientists working in the history of religions would ever try to make the concepts of these traditions into resources for contemporary critical theory. (50) And yet "past Western thinkers and their categories are never quite dead for us in the same way. South Asian(ist) social scientists would argue passionately with a Marx or a Weber without feeling any need to historicize them or to place them in their European intellectual contexts".

(48) By contrast, however, the effects of critical theory on the study of nonWestern religions has not only been far more modest, in many cases it seems also to have had precisely the opposite effect
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