问题 填空题

(9分)化学与人类生活密切相关。(1)厨房中的下列物品,所使用的主要材料属于天然纤维的是    (填字母序号)。

             

A.塑料保鲜膜             B.橡胶手套               C.棉布围裙 

(2)下列食物中,能提供大量维生素的是     (填字母序号)

(3)加碘盐中“碘” 是指       (填“元素”或“分子”),身体中一旦缺碘,可能患有的疾病是       (填“甲状腺肿大”或“骨质疏松”)。

(4)厨房中能用来除水垢的物质是       (填“食醋”或“食盐水”)。

(5)厨房中的下列物质在水中能形成溶液的是       (填字母序号)。

A.调和油       B.食盐         C.面粉         D.白糖

(6)良好的家居环境带来美好的生活。

①房屋装修后,可在室内放一些活性炭来吸收装修材料释放出的甲醛、苯等有毒气体,这是利用活性炭的       性。

②下图所示的“火立熄”是一种新型的家用灭火用品。“火立熄”接触到火焰3—5秒后炸开,释放的粉末覆盖在燃烧物上,同时放出不可燃气体,使火焰熄灭。“火立熄”的灭火原理是   (填标号)。

A.清除可燃物      B.使燃烧物与氧气隔绝     C.降低燃烧物的着火点

(7)汽车是现代生活中常见的一种交通工具。

①喷漆可以延缓汽车钢铁外壳的锈蚀,其防锈原理是隔绝             

②我国已推广使用车用乙醇汽油,它是在汽油中加入适量的乙醇,作为汽车的燃料。

下列叙述正确的是        (填字母)。

A.乙醇汽油是一种新型的化合物   

B.乙醇可通过粮食发酵的方法制得

C.使用乙醇汽油能减少有害气体的排放

D.乙醇和汽油都是可再生能源

用天然气作为机动车的燃料是目前国家大力提倡的,天然气的主要成分是甲烷,甲烷

燃烧的化学方程式为                            

④汽车生产过程中需要各种金属,其中用量最大的是铁和铝。工业上炼铁的简要流程如下:

请写出步骤Ⅰ、Ⅱ、Ⅲ的化学反应方程式                           

                                                          

答案

(1)C (2)A (3)元素   甲状腺肿大 (4)食醋  (5)BD

(6)①吸附   ②B (7)①氧气和水  ②BC   ③ CH4+2O2 CO2+2H2O

④ C+O2 CO2  C + CO2 2CO  3CO + Fe2O3 2Fe +3CO2

(1)厨房中的下列物品,所使用的主要材料属于天然纤维的是:棉布围裙;

(2)水果中富含大量的维生素;

(3)加碘盐中的碘是指碘元素,身体中一旦缺碘,可能患有的疾病是甲状腺肿大;

(4)水垢的主要成分是碳酸钙,碳酸钙能和酸反应,所以厨房中能用来除水垢的物质是食醋;

(5)食盐和蔗糖能溶于水形成溶液,而面粉和水形成的悬浊液,调和油和水形成的是乳浊液;

(6)①房屋装修后,可在室内放一些活性炭来吸收装修材料释放出的甲醛、苯等有毒气体,这是利用活性炭的吸附性;

②“火立熄”接触到火焰3-5秒后炸开,释放的粉末覆盖在燃烧物上,同时放出不可燃气体,使火焰熄灭.是利用使燃烧物与氧气隔绝从而达到灭火;

(7)①喷漆可以延缓汽车钢铁外壳的锈蚀,其防锈原理是隔绝氧气和水;

②我国已推广使用车用乙醇汽油,它是在汽油中加入适量的乙醇,作为汽车的燃料.乙醇可通过粮食发酵的方法制得,使用乙醇汽油能减少有害气体的排放;而乙醇汽油是一种混合物;汽油是不可再生能源;

③用天然气作为机动车的燃料是目前国家大力提倡的,天然气的主要成分是甲烷,甲烷燃烧的化学方程式为:CH4+2O2 CO2+2H2O

④焦炭和氧气反应生成二氧化碳,化学反应方程式:C+O2 CO2;碳和二氧化碳在高温条件下生成一氧化碳,化学反应方程式:C + CO2 2CO;一氧化碳和氧化铁反应生成铁和二氧化碳,化学反应方程式:3CO + Fe2O3 2Fe +3CO2

填空题

Though hardly as unwelcome as death or taxes, college entrance exams are just as inevitable and almost as dreaded by high school students.
As the testing dates loom for juniors and seniors for the SAT (formerly called the Scholastic Assessment Test) and the American College Test, or ACT, most students are looking for an edge, any edge, in the competition.
And as the number of homes with computers continues to rise, test publishers and software developers have been quick to recognize a growing niche. With the market for test preparation materials at all levels estimated at $540 million annually, they have jumped on the tech bandwagon to produce computerized tutorials that promise to boost scores.
(41) " We believe that it’s important for a student to be prepared to take the tests, " notes Don Powers, a research scientist at the Educational Testing Service in Princeton, N. J. , the organization that administers the SAT for the College Board. " It’s important to know how to take the test so that you won’t get a score that’s lower than you deserve. " But, he adds, " none of the rigorous scientific evidence that we have seen supports these promises" to raise test scores.
(42)Several points, however, do weigh in favor of software as opposed to traditional test-preparation. Cost is a big one.
(43)Convenience is another, as the College Board points out in touting its new sofware.
A few points to remember when evaluating various test-prep software packages:
(44)The exams, though they may seem mystical to the test taker, are not magic and certainly not random. There is little variation in the strategies the programs use to boost test scores because there is little variation in how the test are developed.
Largely, what differentiates one program from another is the computer interface, which can make the software more—or less—user-friendly, and such features as automated tracking of student progress.
(45)A crash course with test prep software is never an alternative to careful, long-term preparation for taking the exams. Some students are better equipped to respond to the self-paced, self-motivated approach software offers than others, Powers notes.
Although parents may be in the market for what they consider " serious " study aids, their children, who are the ones taking the tests, may appreciate the programs that offer a little humor.
Finally, as programs frequently point out, the SAT and ACT, while important to college admissions officers, are only one element of a successful college application.
[A] A test prep course with a live instructor can cost as much as $700. Test-prep software costs $30 to $80.
[B] Most of the programs, in fact, emphasize the importance of " guessing strategies " and eliminating unlikely answers to improve scores. Many students often succeed in exams in this way.
[C] Unlike many programs, this one can give you a quick, easy and comfortable way to achieve a high score. Such programs can turn your dream passing exams into reality.
[D] " I would rather use the program than take a preparation course, because I could do this on my own time and in my own home, " notes one student in the College Board materials.
[E] Although at least one of the test programs asks you how long you have to prepare to take the examination in order to customize the learning curve, all recommend spending a period of weeks, not hours, using the software.
[F] But though many programs offer money-back guarantees, professional test writers tend to scoff at those claims. In their mind, such programs overemphasize its functions.
[G] SAT and ACT is popular with the international students, especially Asian students. Many Asian students chase their dream through SAT and ACT.

判断题