问题 实验题

为了比较硫与碳的非金属性的强弱,某同学想通过比较两种元素的最高价氧化物对应的水化物的酸性强弱来证明硫与碳的非金属性的强弱,采用下图中的甲、乙装置进行探究,请你帮助他完成下列问题

(1)仪器A中应盛放的药品是___________,仪器B中应盛放的药品是______________,装置乙中应盛放的药品是________________。

(2)B中发生反应的离子方程式为:_______________________________;在装置乙中观察到的现象是:__________________________。

(3)该实验能证明硫与碳的非金属性的强弱的理论依据是: __________________________________。

答案

(1)稀H2SO4;Na2CO3(或可溶性碳酸盐);澄清石灰水

(2)CO32-+2H+==CO2↑+H2O;澄清石灰水变浑浊

(3)由H2SO4制H2CO3即由强酸制弱酸,S的最高价氧化物对应水化物的酸性强,故S的非金属性比C强

单项选择题
单项选择题

Jan Hendrik Schon’s success seemed too good to be true, and it was. In only four years as a physicist at Bell Laboratories, Schon, 32, had co-authored 90 scientific papers—one every 16 days—detailing new discoveries in superconductivity, lasers, nanotechnology and quantum physics. This output astonished his colleagues, and made them suspicious. When one co-worker noticed that the same table of data appeared in two separate papers—which also happened to appear in the two most prestigious scientific journals in the world, Science and Nature—the jig was up. In October 2002, a Bell Labs investigation found that Schon had falsified and fabricated data. His career as a scientist was finished. Scientific scandals, which are as old as science itself, tend to follow similar patterns of presumption and due reward.

In recent years, of course, the pressure on scientists to publish in the top journals has increased, making the journals much more crucial to career success. The questions are whether Nature and Science have become too powerful as arbiters of what science reaches to the public, and whether the journals are up to their task as gatekeepers.

Each scientific specialty has its own set of journals. Physicists have Physical Review Letters, neuroscientists have Neuron, and so forth. Science and Nature, though, are the only two major journals that cover the gamut of scientific disciplines, from meteorology and zoology to quantum physics and chemistry. As a result, journalists look to them each week for the cream of the crop of new science papers. And scientists look to the journals in part to reach journalists. Why do they care Competition for grants has gotten so fierce that scientists have sought popular renown to gain an edge over their rivals. Publication in specialized journals will win the acclaims from academics and satisfy the publish-or-perish imperative, but Science and Nature come with the added bonus of potentially getting your paper written up in The New York Times and other publications.

Scientists tend to pay more attention to the big two than to other journals. When more scientists know about a particular paper, they’re more apt to cite it in their own papers. Being oft-cited will increase a scientist’s "Impact Factor", a measure of how often papers are cited by peers. Funding agencies use the "Impact Factor" as a rough measure of the influence of scientists they’re considering supporting.

The achievements of Jan Hendrik Schon turned out to be ().

A. surprising

B. inconceivable

C. praiseworthy

D. fraudulent