问题 单项选择题 B1型题

药物性龈炎是()

A.牙槽骨吸收、牙周袋形成

B.牙龈红肿、龈袋形成

C.剥脱性龈病损

D.牙龈组织弥漫性增生,表面呈颗粒结节状

E.龈缘及龈 * * 坏死

答案

参考答案:D

阅读理解

In a great many cities, hundreds of people ride bikes to work every day. In New York, some bike riders have even formed a group called Bike for a Better City. They declare that if more people rode bikes to work, there would be fewer automobiles in the downtown part of the city and so less dirty air from car engines.

For several years, this group had been trying to get the city government to help bike riders. For example, they want the city to draw special lanes(车道) for bikes on some of the main streets, because when bike riders must use the same lanes as cars there are accidents. Bike for a Better City feels that if there were special lanes, more people would use bikes.

But no bike lanes have been drawn. Not everyone thinks it is a good idea—they say it will slow traffic. Some store owners on the main streets don’t like the idea—they say that if there is less traffic, they will have less business.

The city government has not yet decided what to do. It wants to keep everyone happy. On weekends, Central Park—the largest place open ground in New York— is closed to cars, and the roads may be used by bikes only.

小题1:In New York, a group of bike riders__________.

A.are keeping practicing for health

B.have no cars of their own

C.are complaining there are not enough buses

D.are trying to settle the problem of air pollution小题2:The bike riders suggest that __________.

A.bikes should be used instead of cars

B.bike lanes should be drawn

C.fewer buses or cars should be used

D.the number of special lanes should be decreased小题3:The advantage of the special lanes is that__________.

A.they will make cars and buses run slowly

B.they will make it easier for bike riders to go to parks

C.they will make the city more beautiful

D.they will prevent accidents

实验题

(12分)某校化学小组学生利用下图所示装置进行“乙二酸晶体受热分解”的实验,并验证分解产物中有CO2和CO。(图中夹持装置及尾气处理装置均已略去)

(1)装置C中盛放NaOH溶液的作用是                                     

(2)①证明分解产物中有CO2的现象是                                      

②证明分解产物中有CO的现象是                                           

(3)实验结束后,装置F中黑色氧化铜变为红色固体。简述检验红色固体中是否含有Cu2O的实验方法(已知Cu2O溶于稀硫酸生成铜单质和硫酸铜):                      

(4)①草酸和草酸钠(Na2C2O4)可以在酸性条件下被KMnO4、MnO2氧化。KMnO4和草酸钠在稀硫酸中反应的离子方程式是                                       。

②实验室常用草酸钠标定KMnO4溶液。操作如下:准确称取0.2000g草酸钠,放入锥形瓶中,加100mL稀硫酸溶解,用配置好的KMnO4溶液滴定。当加入1滴KMnO4溶液后,锥形瓶中溶液立即由无色变为紫红色,且30s不褪色,即达到滴定终点。重复上述滴定操作三次,实验数据如下表所示。

 滴定前第一次终点第二次终点第三次终点
滴定管液面刻度0.00mL16.02mL16.00mL16.01mL
KMnO4溶液的物质的量浓度的计算式是