问题 选择题

E是非金属性最强的元素,M是E的气态氢化物,在固定体积的密闭容器中,气体M存在如下关系:xM(g)Mx(g),反应物和生成物的物质的量随时间的变化关系如图。下列说法正确的是    (  )

A.该反应的化学方程式是2HF(HF)2

B.平衡时混合气体的平均摩尔质量是33.3

C.t1时刻,保持温度不变,再充入1 mol M,重新达到平衡时,将增大

D.M的沸点比同主族下一周期元素的气态氢化物沸点低

答案

答案:C

由图像知反应物和生成物的化学计量数之比为3:1,故其化学方程式为3HF(HF)3,A错。平衡混合气体中含2 mol HF、1 mol (HF)3=(2 mol×20 g·mol-1+1 mol×60g·mol-1)÷3 mol=33.3 g·mol-1,选项B中漏写单位而错。选项C相当于对体系实施加压,增大压强有利于反应正向进行,故比值增大,C正确。由于HF分子间存在氢键易形成缔合分子,故其沸点比HCl高,D错。

阅读理解
Cooler temperatures, attractive colors, smaller crowds autumn is the perfect time for travel and tourism. Here, three places are listed as the best fall trip destinations. Don’t worry if you can’t go to these places. By reading this page, we hope to take you on grand tour and let you experience fun and culture around the world.
Cannstatter Volkfest, Stuttgart, Germany
Stuttgart’s Cannstatter Volkfest is listed as the world’s second largest beer-drinking event–following Munich’s Oktoberfest. But it is considered Germany’s more authentic celebration of local heritage and, of course, beer.
Started as an agricultural fair in 1818–a symbolic 24-meter-high “fruit column” pays homage to the past–the three-week festival (from September 23 to October 9 this year) features live music, a re-created Alpine village, and carnival(狂欢节) rides.
In addition, Stuttgart is recognized as a global car capital. Both the Mercedes-Benz and Porsche museums are worth a visit.
 
Churchill, Manitoba, Canada
Here in the northern Canadian town at Hudson Bay, visitors can see the area’s most famous fall residents–polar bears.
More than a thousand of the world’s largest land carnivores migrate through the “polar bear capital of the world” during October and November, when the first ice forms on the edge of Hudson Bay. 
The frozen conditions make it easier for hungry bears to hunt for seals (by walking instead of swimming).
Under the snowy, winter weather, visitors can hardly have too many clothes to put on. Insulated boots, jackets, and gloves; layered clothing; thermal underwear; and woolen socks and hats are required.
 
Dublin, Ireland
The Ireland’s capital and largest city is a center for arts, entertainment, culture and commerce.
With few tourists and lower temperatures, fall is the ideal season for walking the historic Georgian streets and cruising the River Liffey.
Visitors can explore the city’s 20 square kilometers of public gardens, nature reserves, and parks, including St. Stephen’s Green, which borders Grafton Street, one of the world’s most expensive retail locations.
  Along the way, enjoy traditional, paper-wrapped fish and chips at Leo Burdock.
  Healthier eats will be on the menu on October 31, when more than 12,000 runners are expected for the National Lottery Dublin Marathon, named “the Friendly Marathon” for the affable crowds cheering there.
小题1:The passage is presented for those who           .
A.care for fun and culture around the world
B.have planned to go for traveling this autumn
C.hate to have their holidays in other seasons
D.have not ever been to Europe and America
小题2:If you spend your holidays on October 31, you may          .
A.enjoy live music at the beer – drinking festival
B.watch polar bears hunt seals
C.taste traditional, paper – wrapped fish and clips
D.win a prize in “the Friendly Marathon”
小题3:According to the passage, we can know that         .
A.Car exhibitions will be held for two months.
B.It’s not necessary to take more clothes with you to Churehill, Martitoba
C.The beer – drinking event in German dates from the eighteenth century
D.Your favourite goods might be available in the expensive shop in Dublin
小题4:The passage is probably taken from the column of        in a newspaper.
A.economicsB.scienceC.tourismD.fashion
单项选择题