问题 填空题

“富煤、贫油、少气”是我国能源发展面临的现状。随着能源的日益紧张,发展“煤化工”对我国能源结构的调整具有重要意义。下图是煤化工产业链之一。

“洁净煤技术”研究在世界上相当普遍,科研人员通过向地下煤层气化炉中交替鼓入空气和水蒸气的方法,连续产出热值很高的煤炭合成气,其主要成分是CO和H2。CO和H2可作为能源和化工原料,应用十分广泛。

(1)已知:C(s)+O2(g)=CO2(g)            ΔH1=-393.5 kJ·mol–1          

C(s)+H2O(g)=CO(g)+H2(g)      ΔH2=+131.3 kJ·mol–1          ②

则反应CO(g)+H2(g) +O2(g)= H2O(g)+CO2(g),ΔH= _________kJ·mol–1。在标准状况下,33.6 L的煤炭合成气(设全部为CO和H2)与氧气完全反应生成CO2和H2O,反应中转移______mole

(2)在一恒容的密闭容器中,由CO和H2合成甲醇:CO(g)+2H2(g)CH3OH(g)

①下列情形能说明上述反应已达到平衡状态的是_______

a.体系压强保持不变

b.密闭容器中CO、H2、CH3OH(g)3种气体共存

c.CH3OH与H2物质的量之比为1:2

d.每消耗1 mol CO的同时生成2molH2

②CO的平衡转化率(α)与温度、压强的关系如图所示。

A、B两点的平衡常数_____(填“前者”、“后者”或“一样”)大;达到A、C两点的平衡状态所需的时间tA      tC(填“大于”、“小于”或“等于”)。

在不改变反应物用量的情况下,为提高CO的转化率可采取的措施是_____________(答出两点即可)。

(3)工作温度650℃的熔融盐燃料电池,是用煤炭气(CO、H2)作负极燃气,空气与CO2的混合气体为正极燃气,用一定比例的Li2CO3和Na2CO3低熔点混合物做电解质,以金属镍(燃料极)为催化剂制成的。负极的电极反应式为:CO + H2-4e+ 2CO32= 3CO2+H2O;则该电池的正极反应式为____________。

答案

(1) -524.8 (2分)    3 (2分)

(2) ①a d (2分)

②一样 (2分)   大于 (2分)  降温、加压、将甲醇从混合体系中分离出来 (2分)

(3) O+ 4e– + 2CO2 = 2CO32– (2分)

题目分析:(1)根据盖斯定律,将两个热化学方程式相减,即①-②得:CO(g)+H2(g) +O2(g)= H2O(g)+CO2(g),则ΔH=ΔH1-ΔH2=-393.5 kJ·mol–1-131.3 kJ·mol–1=-524.8kJ·mol–1。CO→CO2转移2mole,H2→H2O转移2mole,则1.5molCO与H2的混合气体与O2完全反应生成CO2和H2O时,转移3mol电子。(2)①a、正反应为气体分子数减小的反应,当压强不变时,说明各物质浓度不再变化,反应达到平衡状态;b、CO、H2、CH3OH(g)3种气体共存时,不能确定浓度是否会发生变化,即不能确定是否在一定达到平衡状态;c、CH3OH与H2物质的量之比为1:2,不能确定其浓度不变,因此,不能确定是否在一定达到平衡状态;;d、当消耗1 mol CO的同时生成2molH2时,说明正逆反应速率相等,即反应达到平衡状态。②A、B两点的温度相同,所以平衡常数相等;从图像看出,A、C两点的转化率相等,而C点的温度高,反应速率大,则到达平衡的时间短。从图像看出,温度降低CO的转化率增大;该反应为气体分子数减小的反应,加压可使平衡向正反应方向移动,CO的转化率增大;c(CH3OH)减小,平衡也会向正反应方向移动,CO的转化率增大。(3)燃烧电池的正极为O2得电子,考虑到电池总反应为H2和CO与O2反应生成CO2和H2O,而负极有CO32–参与反应,则正极应该有CO32–生成,故正极反应式为:O+ 4e– + 2CO2 = 2CO32–

填空题
单项选择题

People can get emotional about immigration. Bill O’Reilly, a talk-show host, devoted a recent segment to the story of an illegal alien who got drunk and accidentally killed two attractive white girls with his car. If only he had been deported for previous misdemeanours, Mr. O’Reilly raged, those girls would still be alive. Another talk-show host, Geraldo Rivera, during an on-air shout-joust(争吵) with Mr. O’ Reilly, denounced his demagogic choice of story-angle as" a sin".

President George Bush tried again this week to bring a more rational tone to the debate. He urged the new Democratic Congress to revive the immigration reforms that the old Republican Congress killed last year. His proposal was broadly the same as before. He said he wanted to make it harder to enter America illegally, but easier to do so legally, and to offer a path to citizenship for the estimated 12m illegals who have already snuck in.

The first part faces few political hurdles and is already well under way. Mr. Bush expects to have doubled the number of Border Patrol agents by the end of next year. The new recruits are being trained. And to defend against the invading legions of would-be gardeners and hotel cleaners, the frontier is also equipped with high-tech military gizmos(小发明), such as unmanned spy planes with infra-red(红外) cameras. This may be having some effect. Mr. Bush boasted that the number of people caught sneaking over the border had fallen by nearly 30% this year.

And the controversial part of Mr. Bush’s immigration package--allowing more immigrants in and offering those already in America a chance to become legal -- is still just a plan. House Republicans squashed it last year. Mr. Bush senses a second chance with the new Democratic Congress, but Democrats, like Republicans, are split on the issue. Some, notably Ted Kennedy, think America should embrace hard- working migrants. Others fret that hard-working migrants will undercut the wages of the native-born.

Mr. Bush would like to see the pro-immigrant wings of both parties work together to give him a bill he can sign. The Senate is expected to squeeze in a debate next month. The administration is trying to entice law-and-order Republicans on board; a recent leaked memo talked of substantial fines for illegals before they can become legal and" much bigger" fines for employers who hire them before they do.

The biggest hurdle, however, may be the Democrats’ reluctance to co-operate with Mr. Bush. Some figure that, rather than letting their hated adversary share the credit for fixing the immigration system, they should stall until a Democrat is in the White House and then take it all. So there is a selfish as well as a moral argument for making a deal.

The underlined word "misdemeanours" (Line 3, Paragraph 1) can be replaced by ()

A. severe crimes

B. homicide

C. misbehaviors

D. nonsense doings