问题 问答题

如图所示,将甲、乙两个装有不同物质的针筒用导管连接起来,将乙针筒内的物质压到甲针筒内,进行下表所列的不同实验(气体在同温同压下测定).

则下列说法正确的是(  )

实验序号甲针筒内物质乙针筒内物质甲针筒的现象
110mLAgNO3溶液10mLNH3生成白色沉淀,后变色
220mLHBr10mL Cl2
330mLNO10mLO2
415mlCl240mLNH3活塞有移动,产生白烟

A.实验1中沉淀最终变为红褐色

B.实验2中甲针筒内的现象是气体颜色变深,且活塞向内移动

C.实验3中甲针筒内气体颜色变深,活塞向内压缩

D.实验4中甲针筒内除有白烟产生外,活塞最终可能向内压缩到尽头

答案

A、AgNO3+NH3?H2O═AgOH↓+NH4NO3,AgOH为白色沉淀,氨气过量AgOH+2NH3?H2O═[Ag(NH32]OH+2H2O,沉淀消失,故A错误;

B、发生反应2HBr+Cl2=Br2+2HCl,二者恰好反应,溴挥发形成蒸汽,甲针筒内气体颜色变深,气体的物质的量增大,活塞向外移动,故B错误;

C、发生反应2NO+O2=2NO2,同时存在2NO2?N2O4,甲针筒内气体颜色变深,气体的物质的量减小,活塞向内压缩,故A正确;

D、氯气与氨气体积之比为15mL:40mL=3:8,发生反应3Cl2+8NH3=N2+6NH4Cl,生成氮气15mL×

1
3
=5mL,有白烟产生外,活塞最终不可能向内压缩到尽,故D错误;

故选C.

判断题
单项选择题

When it comes to suing doctors, Philadelphia is hardly the city of brotherly love. A combination of sprightly lawyers and sympathetic juries has made Philadelphia a hotspot for medical-malpractice lawsuits. Since 1995, Pennsylvania state courts have awarded an average of $ 2m in such cases, according to Jury Verdict Research, a survey firm. Some medical specialists have seen their malpractice insurance premiums nearly double over the past year. Obstetricians are now paying up to $104,000 a year to protect themselves.

The insurance industry is largely to blame. Carol Golin, the Monitor’s editor, argues that in the 1990s insurers tried to grab market share by offering artificially low rates (betting that any losses would be covered by gains on their investments). The stock-market correction, coupled with the large legal awards, has eroded the insurers’ reserves. Three in Pennsylvania alone have gone bust.

A few doctors--particularly older ones--will quit. The rest are adapting. Some are abandoning litigation-prone procedures, such as delivering babies. Others are moving parts of their practice to neighboring states where insurance rates are lower. Some from Pennsylvania have opened offices in New Jersey. New doctors may also be deterred from setting up shop in litigation havens, however prestigious.

Despite a Republican president, tort reform has got nowhere at the federal level. Indeed doctors could get clobbered indirectly by a Patients’ Bill of Rights, which would further expose managed care companies to lawsuits. This prospect has fuelled interest among doctors in Pennsylvania’s new medical malpractice reform bill, which was signed into law on March 20th. It will, among other things, give doctors $ 40m of state funds to offset their insurance premiums, spread the payment of awards out over time and prohibit individuals from double dipping--that is, suing a doctor for damages that have already been paid by their health insurer.

But will it really help Randall Bovbjerg, a health policy expert at the Urban Institute, argues that the only proper way to slow down the litigation machine would be to limit the compensation for pain and suffering, so-called "non-monetary damages". Needless to say, a fixed cap on such awards is resisted by most trial lawyers. But Mr Bovbjerg reckons a more nuanced approach, with a sliding scale of payments based on well-defined measures of injury, is a better way forward. In the meantime, doctors and insurers are bracing themselves for a couple more rough years before the insurance cycle turns.

Nobody disputes that hospital staff make mistakes: a 1999 Institute of Medicine report claimed that errors kill at least 44,000 patients a year. But there is little evidence that malpractice lawsuits on their own will solve the problem.

We can learn from the beginning of the text that doctors in Philadelphia()

A. are often overcharged

B. flee out of the hot city

C. are likely to be sued

D. enjoy a high prestige