问题 推断题

A、B、C三种物质都含有同一种元素,B是单质,A、C都是氧化物,C是一种黑色固体物质,且反应②发生时可观察到剧烈燃烧,火星四射.它们之间有如图所示的转化关系(部分物质已略去),请回答:

(1)写出C的化学式                   

(2)写出反应①的化学方程式:                  ;现象为                           

(3)写出反应②的化学方程式                                  

答案

(1)Fe3O4;(2)Fe+CuSO4═FeSO4+Cu,铁钉表面出现一层红色固体,溶液由蓝色变为浅绿色;

(3)3Fe+2O2 Fe3O4

题目分析:本题的解题突破口是反应②发生时可观察到剧烈燃烧,火星四射,生成的C是黑色固体,则C是四氧化三铁;A是氧化物,能与木炭在高温下反应生成单质B,则B是铁,A可能是氧化铁,代入框图,推断合理;(1)C是四氧化三铁,故填:Fe3O4;(2)B是铁,能与硫酸铜反应生成硫酸亚铁,该反应进行时能看到铁钉表面有红色固体析出,溶液由蓝色变为浅绿色,故填:Fe+CuSO4═FeSO4+Cu,铁钉表面出现一层红色固体,溶液由蓝色变为浅绿色;(3)铁与氧气反应生成四氧化三铁,故填:3Fe+2O2 Fe3O4

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Passage Four

The face of the 21st century is already growing in a laboratory. Getting a piece of the new look could soon be as simple as writing a cheque.
Scientists in recent years have made giant leaps in the artificial production of skin, bones and tissue. While their research has been motivated by a desire to help accident and medical victims, their work is about to go commercial.
The burgeoning (萌芽) cosmetic surgery market has snapped up the technological advances. By the turn of the 21st century, changing your face or improving your body will be limited not by your imagination or desire, but by the size of your bank account.
And there is even work being clone on that, with the costs of cosmetic surgery being cut to make it affordable and accessible for the average woman and her partner.
"It’s no longer a vanity thing, it’s simply making use of the available technology to improve those parts of the body you might not be happy with," Cindy Clovetti, a Toronto-based skin and beauty care expert, said. "People who 10 years ago said they would never use a computer and would never get a boob job (胸部整形手术) are now surfing the web getting the latest information for their next operation. "
Latest figures in the United States indicate the number of patients receiving cosmetic surgery in 12 months will top the magic million within two years (there were 850 000 last year), while the number of men seeking image-improving operations has increased 35 percent in the past four years.
Breast implants are now very much a bread-and-butter job for many cosmetic surgeons and the big advances have been made in the development of bone implants which can produce instant high cheek bones, sculpture better shaped noses and ears and give men the chisel-shaped jaw that is always a sure-fire (必定成功的) chick-magnet (吸引女人的东西).
British futurologist Ian Pearson speculates that by 2020, up to 96 percent of body weight will be replaceable with the brain being the only organ not interchangeable. "By 2020 you could have a new face, or new skim. and by 2030 a fully working replacement body part. By the end of the 21st century, people will be able to get an entirely new body. "

The sentence "...changing your face or improving your body will be limited not by your imagination or desire, but by the size of your bank account. " (Para. 3) means that

A.if you want to change your face or improve your body, you can do it easily

B.if you have enough money, you can undergo any cosmetic surgery

C.the technology will advance beyond your imagination

D.the technology will develop rapidly if there is enough fund