为探究碱式碳酸铜[化学式为Cu2(OH)2CO3]加热分解的产物,取一定量样品进

题型:实验题

问题:

为探究碱式碳酸铜[化学式为Cu2(OH)2CO3]加热分解的产物,取一定量样品进行加热,生成黑色固体,并产生能使澄清石灰水浑浊的气体。思考并回答:

(1)产生的气体中肯定含有___________。

(2)在不用任何试剂的条件下,你判断有水生成的方法是:观察到试管壁有_____________。

(3)对生成的黑色固体物质的猜想是:①可能是炭黑;②可能是铁或四氧化三铁;③可能是氧化铜。你认为上述猜想没有科学依据的是(填编号)________,理由是_________。请你设计一个方案,证实你的第③个猜想:

考点:设计实验和科学探究
题型:实验题

信念属于态度的()成分。

A.行为

B.行为倾向

C.情感

D.认知

题型:实验题

m阶B+树的每个结点至多有()个子女。

题型:实验题

加油卡加油方式是指客户到发卡点付款,购买一定金额的加油专用充值卡,凭卡加油的结算方式。

题型:实验题

(46) Globalization might be welcomed on many grounds—the economic, political, communicational, and even linguistic ones come readily to mind but it also has some unfortunate side effects that might prove deadly to the very future of mankind. This is no mere surmise of congenital misanthropes, but the expressed fear of some who are otherwise well disposed to it. Thus Thomas Friedman, in an otherwise optimistically minded book, nevertheless, writes as follows:
(47) The more I observed the system of globalization at work, the more obvious it was that it had unleashed forest-crushing forces of development, which if left unchecked had the potential to destroy the environment and uproot culture...
(48) And because globalization as a culturally homogenizing and environment-devouring force is coming on so fast, there is real danger that in just a few decades it will wipe out the ecological and cultural diversity that took millions of years of human and biological forces to produce.
Something is as ominous as all that is a real threat indeed. (49) And yet, despite such apprehensions, Friedman and others who think like him believe that effects of this magnitude can somehow be sidestepped without interfering with the technicizing sweep of globalization. Is that merely wishful thinking or an inability to take in the full import of his own words
As Friedman points out, the globalization threat is at once to nature and to culture: to the environment and the whole ecological variety of plants and animals, as well as to the quality of human life and the cultural diversity on which it depends. Damage to nature eventually translates itself as damage to culture, and vice versa. The fate of many ancient civilizations that collapsed because they outgrew their natural resources is historical proof of that fact. Our modern civilization is subject to the same self-limiting conditions. (50) Thus, if all agriculture is reduced to an agribusiness industry, then the diversified countryside landscape that humans have created since the Neolithic revolution will become a monocultural ecological desert, for with it will disappear a host of animal and plant species as well as a whole rural way of life with its myriad varieties of folk cultures that have been carried on for millennia. The loss of natural species through the destruction of their natural habitat is paralleled step by step by the loss of cultural "species" through the elimination of their social habitat, which is rooted in a natural environment. The clearing of jungles does not merely exterminate the animals living there, but also the native people whose homes have been there for countless generations.

题型:实验题

邀请对方出席或是前来我方做客时所要遵守的礼仪叫做()。

A.邀约的礼仪

B.赴宴的礼仪

C.来往的礼仪

D.交往的礼仪

更多题库