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实施以减少能源浪费和降低废气排放为基本内容的节能减排政策，是应对全球气候问题、建设资源节约型、环境友好型社会的必然选择。化工行业的发展必须符合国家节能减排的总体要求。试运用所学知识，解决下列问题：

⑴已知某反应的平衡表达式为：

它所对应的化学反应方程式为：

⑵利用水煤气合成二甲醚的三步反应如下：

①2H2（g）+CO（g）CH3OH（g）；ΔH=－90.8kJ·mol

②2CH3OH（g）CH3OCH3（g）+H2O（g）；ΔH=－23.5kJ·mol

③CO（g）+H2O（g）CO2（g）+H2（g）；ΔH=－41.3kJ·mol

总反应：3H2（g）+3CO（g）CH3OCH3（g）+CO2（g）的ΔH=__________

(3)煤化工通常通过研究不同温度下平衡常数以解决各种实际问题。已知等体积的一氧化碳和水蒸气进入反应器时，会发生如下反应：CO（g）+H2O（g）H2（g）+CO2（g），该反应平衡常数随温度的变化如下表所示：

温度/℃400500800
平衡常数K9.9491
 

该反应的正反应方向是反应（填“吸热”或“放热”），若在500℃时进行，设起始时CO和H2O的起始浓度均为0.020mol/L，在该条件下，CO的平衡转化率为：。

(4)从氨催化氧化可以制硝酸，此过程中涉及氮氧化物，如NO、NO2、N2O4等。

对反应:N2O4（g）2NO2（g）△H>0，在温度为T1、T2时，平衡体系中NO2的体积分数随压强变化曲线如图所示。下列说法正确的是。

A．A、C两点的反应速率：A＞C

B．A、C两点气体的颜色：A深，C浅

C．B、C两点的气体的平均相对分子质量：B＜C

D．由状态B到状态A，可以用加热的方法

E．A、C两点的化学平衡常数：A＞C

(5)CO2(g)+3H2(g)CH3OH(g)+H2O(g)△H=－49.0kJ·mol－1。现在温度、容积相同的3个密闭容器中，按不同方式投入反应物，保持恒温、恒容，测得反应达到平衡时的有关数据如下。下列说法正确的是

答案

⑴C（s）+H2O（g）CO（g）+H2（g）（2分）

⑵-246.4kJ/mol（2分）⑶放热（1分），75%（2分）⑷D（2分）(5)BDE(2分)

⑴由平衡常数表达式可知：生成物及其状态为CO（g）和H2（g），反应物及其状态为H2O（g），再由质量守恒得反应物还有C（s），方程式为C（s）+H2O（g）CO（g）+H2（g），答案：C（s）+H2O（g）CO（g）+H2（g）；⑵①×2+②+③得总方程式，△H=－90.8kJ·mol-1×2－23.5kJ·mol-1－41.3kJ·mol-1=-246.4kJ·mol-1,答案：-246.4kJ·mol-1；⑶升高温度，平衡常数减小，反应进行程度越小，平衡向逆反应移动，升高温度平衡向吸热方向移动，故正反应为放热反应；

设CO的浓度变化量为c，三段式法用c表示出平衡时各组分个浓度，

CO（g）+H2O（g）H2（g）+CO2（g），

起始（mol·L－1）：0.020.02000

转化（mol·L－1）：cccc

平衡（mol·L－1）：0.02-c0.02-ccc

代入500℃时反应平衡常数有k===9，解得c=0.015，

CO的最大所以转化率为××100%=75%，

⑷A．由图象可知，A、C两点都在等温线上，C的压强大，则A、C两点的反应速率：A＜C，A错误；

B．由图象可知，A、C两点都在等温线上，C的压强大，与A相比C点平衡向逆反应进行，向逆反应进行是减小由于压强增大导致浓度增大趋势，但到达平衡仍比原平衡浓度大，平衡时NO2浓度比A的浓度高，NO2为红棕色气体，则A、C两点气体的颜色：A浅，C深，B错误；C．B、C两点二氧化氮的体积分数相同，则混合气体的平均相对分子质量相同，C错误；

D．在相同压强下，升高温度，平衡向逆反应方向移动，则二氧化氮的体积分数增大，所以由状态B到状态A，可以用加热的方法，故D正确；E由图象可知，A、C两点都在等温线上，平衡常数只受温度影响，温度相同平衡常数相同，所以化学平衡常数KA=KC，E错误;

⑸实验1和实验2是全等等效平衡，实验3相当于实验2放大两倍后将体积压缩，A、CH3OH的平衡浓度2C1<C3,A错误；B、实验1从正向建立平衡和实验2从逆向建立平衡，x+y=49.0，B正确；C、该反应是体积缩小的反应，加压后正向移动，2P2>P3，C错误，又P1=P2,2P1>P3，E正确；D、a1+a2=1，a3<a2，（a1+a3）<1，D正确，F错误，选BDE。

单项选择题 A1/A2型题

调配塑料时，为了防止牙托水挥发，必须在玻璃杯上加盖，选用下列哪一种最好（）

A.纸板

B.塑料板

C.蜡片

D.玻璃板

E.用手直接捂住
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单项选择题

Almost everyone agrees that America’s health-care system has the incentives all wrong. Under the present system, doctors and hospitals get paid for doing more, even if added tests, operations and procedures have little chance of improving patients’ health. So what happens when someone proposes that we alter the incentives to reward better care, not more care Well, Rep. Paul Ryan and Republicans found out. No surprise: Democrats slammed them for "ending Medicare as we know it. "

This predictably partisan reaction preying upon the anxieties of retirees—must depress anyone who cares about the country’s future. It is only a slight exaggeration to say that unless we end Medicare "as we know it," America "as we know it" will end. Spiraling health spending is the crux of our federal budget problem. In 1965—the year Congress created Medicare and Medicaid—health spending was 2.6 percent of the budget. In 2010, it was 26.5 percent. The Obama administration estimates it will be 30.3 percent in 2016. By contrast, defense spending is about 20 percent; scientific research and development is 4 percent.

Uncontrolled health spending isn’t simply crowding out other government programs; it’s also dampening overall living standards. Health economists Michael Chernew, Richard Hirth and David Cutler recently reported that higher health costs consumed 35.7 percent of the increase in per capita income from 1999 to 2007. They also project that, under reasonable assumptions, it could absorb half or more of the gain between now and 2083.

Ryan proposes to change that. Beginning in 2022, new (not existing) Medicare beneficiaries would receive a voucher, valued initially at about $ 8,000. The theory is simple. Suddenly empowered, Medicare beneficiaries would shop for lowest-cost, highest-quality insurance plans providing a required package of benefits. The health-care delivery system would be forced to restructure by reducing costs and improving quality. Doctors, hospitals and clinics would form networks; there would be more "coordination" of care, helped by more investment in information technology; better use of deductibles and co-payments would reduce unnecessary trips to doctors’ offices or clinics.

It’s shock therapy. Would it work No one knows, but two things are clear. First, as Medicare goes, so goes the entire health-care system. Medicare is the nation’s largest insurance program, with 48 million recipients and spending last year of $ 520 billion. Second, few doubt that today’s health-care system has much waste: medical care that does no good.

Under Ryan’s plan, incentives would shift. Medicare would no longer be an open ATM; the vouchers would limit total spending. Providers would face pressures to do more with less; there would certainly be charges that essential care was being denied. The Obama administration argues that better results can be achieved by modifying incentives within the existing system. Perhaps. But history suggests skepticism. It’s Ryan’s radicalism vs. President Obama’s remedy policy. Which is realistic and which is wishful thinking Burdened by runaway spending, Medicare "as we know it" is going to end. The only questions are when and on whose terms.

It can be inferred from the passage that Ryan’s plan（）

A. would be readily accepted by the Obama administration

B. is nothing but wishful thinking and thus is unrealistic

C. arises from dissatisfaction with Obama’s health-care reform

D. ignores the essential health-care for old beneficiaries
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