问题 问答题

以石灰石为原料,在一定条件下进行如图实验:

[注:上述实验过程中,气体C过量,尾气D,以适当方式收集]

Ⅰ.写出反应②的化学方程式______,反应基本类型______;

Ⅱ.反应③的实验现象是______,尾气D的成分是______(填化学式);

Ⅲ.某实验兴趣小组对固体B的成分(不考虑石灰石中原有的杂质)进行实验探究:

甲同学认为固体B一定只有氧化钙,其理论依据是______(用化学方程式表示).

乙同学认为固体B除了有氧化锷j还可能有______,为此,他们决定用实验来验证:

实验步骤实验现象实验结论
I.取冷却后的少量固体B于小烧杯中,加入适量的水,并滴加基地酚酞试剂烧杯中放出大量热量,酚酞试剂呈______色固体B中含有氧化钙
II.取冷却后的少量固体B于小烧杯中,滴加适量的______产生大量气泡固体B中含有______
最终得出结论,乙同学的想法更为全面.

答案

Ⅰ.碳酸钙高温能分解生成氧化钙和二氧化碳,所以反应②的反应物是二氧化碳和碳,生成物是一氧化碳,反应条件是高温,所以方程式是:CO2+C

高温
.
2CO,反应物是两种,生成物是一种,属于化合反应;

Ⅱ.碳酸钙高温能分解生成氧化钙和二氧化碳,故A为二氧化碳,B为氧化钙,二氧化碳能与碳反应生成一氧化碳,故C为一氧化碳,一氧化碳具有还原性,能将氧化铜还原为铜,同时生成二氧化碳,所以反应现象是黑色粉末变为红色,D中气体是二氧化碳,如果一氧化碳过量,则D中含有生成的二氧化碳和多余的一氧化碳,所以本题答案为:CO2(或CO、CO2).

Ⅲ.碳酸钙高温能分解生成氧化钙和二氧化碳,所以方程式是:CaCO3

高温
.
CaO+CO2↑,根据固体B中可能含有不反应的碳酸钙,所以可能含有碳酸钙;氧化钙与水反应生成氢氧化钙,属于碱,能使酚酞试液变红;取固体B滴加盐酸,由于碳酸钙与盐酸反应生成氯化钙、水和二氧化碳,所以滴加盐酸后有气泡说明有碳酸钙.

故答案为:I.CO2+C

高温
.
2CO,化合;Ⅱ.黑色固体变红,CO2(或CO、CO2);Ⅲ.CaCO3
高温
.
CaO+CO2↑,碳酸钙,红;稀盐酸,碳酸钙.

完形填空

For each blank in the following passage there are four words or phrases marked A, B, C and D.  Fill in each blank with the word or phrase that best fits the context.

To advertise effectively today, you must abandon the old-school idea of “reaching the masses”. All advertising is local and personal. The key to effective advertising today is to focus on the   50  .

Some are the   51   ways every advertiser could work out. You can print a specific offer of your goods or service on door-hangers and place them on doorknobs in your area. Door-hangers on doorknobs will produce results in direct   52   about the strength of your offer. If you need to reach the drivers, flyer (宣传单) under windshield (挡风玻璃) wipers may have better effect than door-hangers. Imagine, how   53   if you hire someone to be a walking ad or launch a T-shirt advertising,   54  , you can print your products on T-shirts of your   55  . In the early 1970s “Hamp Baker says Drive with Care” was spray-painted on cars, which was a public service ad. Ever since, spray-painted sign has become more and more   56  .

More grand ways are as follows: virtual showroom. Build a website to   57   a virtual showroom. Use it when people call to ask   58   about your company, your products or your services. Also you can even use an old slide projector to put on a nighttime show. They’re   59   effective, and in the long run, cheap. Nothing is quite as powerful as a public   60   that seizes the public’s attention. You can invite a band to give a performance.

61   , you can hire famous models to show it vividly.

Nothing screams “expert” quite as loudly as a book written about a subject. You simply can’t   62   the power of your name on the cover of a book. You might only sell a few copies online, but the copies you give away in your town will make you a fortune. You won’t make money on the book. You’ll make it because of the book.

Of course, word-of-mouth is the best way to promote your   63  . Friends and past customers recommend your products to their family, friends and colleagues. Word-of-mouth works because the   64  is based on previous positive experiences.

50.   A. content                  B. product                           C. individual               D. style

51.   A. strange                  B. common                         C. amusing                D. perfect

52.   A. description           B. decision                          C. discussion             D. permission

53.   A. stupid                     B. funny                               C. impressive            D. ridiculous

54.   A. that is                   B. first of all                        C. as a result             D. generally speaking

55.   A. customers            B. employers                      C. consumers            D. employees

56.   A. expensive              B. valueless                        C. popular                  D. meaningless

57.   A. refer to                  B. serve as                          C. stand for               D. keep off

58.   A. location                 B. business-hours             C. salary                     D. details

59. A. unbelievably         B. consequently                 C. accidentally          D. occasionally

60.   A. speech                            B. sport                                C. debate                            D. performance

61.   A. For example         B. Moreover                       C. However               D. To be exact

62.   A. create                    B. change                                     C. imagine                 D. overuse

63.   A. production            B. friendship                       C. management       D. business

64.   A. information          B. relationship                   C. pronunciation     D. achievement

问答题 简答题