某兴趣小组对铁、锰(Mn)、铜的金属活动性顺序展开了探究.提供的药品:铁片、铜片

题型:问答题

问题:

某兴趣小组对铁、锰(Mn)、铜的金属活动性顺序展开了探究.提供的药品:铁片、铜片、锰片、稀盐酸、硫酸亚铁溶液、硫酸铜溶液、硫酸锰溶液.

请你参与并将以下内容补充完整:

提出假设:小组同学考虑到铁的活动性比铜强,对三种金属的活动性顺序提出如下假设.

假设l:锰>铁>铜    假设2:铁>锰>铜    假设3:______.

设计方案:

(1)验证假设l的实验方案是将锰片、铁片分别放入稀盐酸中,观察现象.

(2)假设2是否成立,小组同学提出了多种实验方案.

方案一是将锰片分别放入硫酸亚铁溶液和硫酸铜溶液中,观察现象;

方案二是______.

(3)验证假设3的实验方案是______.

实验及结论:小组同学通过实验交流后,确认假设1是成立的.验证假设1的实验现象是______.锰与盐酸反应的化学方程式为(反应中锰的化合价为+2价)______.

拓展研究:金属与酸的反应存在某种规律,请你分析下表中的数据,找到对应关系.

等质量(ag)的金属与足量盐酸反应
金属的相对原子质量245655
产生氢气的质量(g)a/12a/28a/27.5
找到的规律______

考点:质量守恒定律金属活动性
题型:问答题

患儿女,10个月,因“腹泻伴呕吐3d,尿量少1d”来诊。排粪7~8次/d,蛋花汤样,略带腥臭。患儿以牛奶喂养为主,乳具较少消毒。既往无腹泻史。查体:T38℃;精神差,哭时泪少,前囟、眼窝凹陷,唇干;心、肺听诊正常;腹平软,按压无哭闹,肠鸣音活跃。粪常规:色黄,有黏液,WBC0~5/HP。血钠140mmol/L,血钾2.8mmol/L,BE-15mmol/L。

失水、代谢性酸中毒纠正后患儿突然抽搐,此时应优先检查 ()

A.脑脊液

B.颅脑CT

C.血糖

D.血钾

E.血钙

F.血镁

题型:问答题

为什么新茶比陈茶好喝?

题型:问答题

外源化合物在体内储存的意义有()。

A.解毒

B.增毒

C.对急性中毒具有保护作用

D.成为血液中游离型毒物的来源

E.没有任何意义

题型:问答题

由于祭祀社稷神是由北向南设祭,所以社稷坛总体形制与太庙相反,即享殿、拜殿及正门均在北,沿正门、享殿、拜殿、五色土方坛为序,由北向南展开。

题型:问答题

Democrats on the Senate Judiciary Committee vented their fury over high gasoline prices at executives of the nation’s five largest oil companies on Wednesday, grilling the oilmen over their multimillion-dollar pay packages and warning them that Congress was intent on taking action that could include a new tax on so-called windfall profits. Such showdowns between lawmakers and oil titans have become a familiar routine on Capitol Hill. But with gas prices nearing $ 4 a gallon, and lawmakers headed home for a weeklong Memorial Day recess where they expect to get an earful from angry constituents, there is added urgency for Congress to appear active.

But while momentum is building for several measures, including a bill that would allow the Organization of the Petroleum Exporting Countries to be sued in American courts under antitrust laws, there is little sign that any of the proposals would do much, if anything, to lower prices quickly. And the oil executives warned that government intervention might only make things worse. Instead, they called on Congress to allow more drilling and exploration for domestic oil.

The increasing urgency to seem aggressive about gasoline prices was apparent on Tuesday when the House voted by an overwhelming 324 to 84 to approve the bill, commonly referred to as NOPEC, which classifies OPEC as a monopoly in violation of the Sherman Antitrust Act. Senate Democrats have included that measure as part of a package of legislation intended to address the high price of gasoline, along with the tax on windfall profits and a measure to tamp down speculation in the oil futures market that many lawmakers think is contributing to the run-up in prices.

At the Judiciary Committee hearing, Democratic senators struggled to have the executives explain how oil prices had risen so high. The senators expressed doubt that basic laws of supply and demand were at work and suggested instead a more sinister combination of monopolistic behavior by oil-producing countries, speculation in the futures markets and sheer corporate greed.

On Monday, President Bush signed a bill temporarily suspending the purchase of crude oil for the nation’s Strategic Petroleum Reserve. Mr. Bush had initially opposed such action but relented after the House and Senate approved the bill by wide margins. Senator Richard J. Durbin, Democrat of Illinois and a p supporter of Senator Baraek Obama’s presidential bid, made a particularly pointed attack, in which he seemed to warn the oil executives that they would soon no longer have such a good friend in the White House. He also suggested that Mr. Bush should be doing more to press the oil companies to help lower prices at the pump, while acknowledging that it would be difficult to pass a windfall profits tax while Mr. Bush was still in office.

According to Democratic senators, which of the following is NOT a factor contributing to soaring oil prices()

A. The basic laws of supply and demand

B. The monopoly of oil-producing countries

C. Speculation in the oil futures markets

D. Oil companies salivating over profits

更多题库