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57. They won’t buy new clothes because they__money to buy a color TV set.

A. save      B. are saving     C. has saved    D. were saving

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56. - Why? Tom, your shirt is so dirty!

- Mum, I _____ my storeroom downstairs。

A. cleaned    B. have worked     C. was cleaning   D. have been cleaning

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55. - I’m sorry, but I shouldn’t have been so rude to you.

- You _____ your temper but that’s OK.

A. have lost   B. had lost       C. did lose     D. were losing

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54. - It is said that another new car factory _____ now.

- Yeah. It _____ one and a half years.

A. is building; takes         B. is being built; will take

C. is built; will take         D. is being built; takes

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53. He will stop showing off, if no notice _____ of him.

A. is taken   B. will be taken    C. takes       D. has taken

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52. - We _____ that you would fix the TV set this week.

- I’m sorry. I __ to, but I’ve been too busy.

A. had expected; had intended       B. are expecting; had intended

C. expect; intend            D. expected; intend

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2、  硫酸根离子的检验(干扰离子可能有:CO32-、SO32-、SiO32-、Ag+、PO43等离子):

待测液澄清液白色沉淀(说明待测液中含有SO42-离子)

[针对性训练]

甲、乙、丙三学生各设计了一个实验,结果各自都认为自己所检测的试样中含有SO42-离子。

(1)甲实验为:

  试样A的无色溶液白色沉淀沉淀不溶解。

乙认为甲的实验不严谨,因为试样A中若含有    离子(仅填一种),也会有此现象。

(2)乙实验为:

  试样B的无色溶液白色沉淀沉淀不溶解。

丙认为乙的实验也不严谨,因为试样B中若含有    离子(仅填一种),也会有此现象。

(3)丙实验为:

  试样C的无色溶液现象I现象II。

若丙方案实验后公认为合理,则回答:试剂I是       ,实验中必须加至     ,此时的现象I是         ;试剂II是       ,此时的现象II是             

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1、硫酸的用途:制过磷酸钙、硫酸铵、硫酸铜、硫酸亚铁、医药、炸药,用于铅蓄电池,作干燥剂、制挥发性酸、作脱水剂和催化剂等。

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3、用含FeS278%的硫铁矿制硫酸,若煅烧时,损失6%的硫,二氧化硫氧化成三氧化硫时损失2%的硫。要制取1t98%的浓硫酸,需这种硫铁矿      t。

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3、环境污染和环境保护:

 (1)环境污染:_________  _________  _________  ___________等。

 (2)工业“三废”:___________  ____________  ______________。

[针对性训练]

1接触法制硫酸时,二氧化硫在接触室中钒触媒的作用下,被空气中的氧气氧化而发生反应:2SO2(g)+ O2(g) 2SO3(g);=-1965kJ/mol,接触室的适宜温度为     。其理由是                                    

工业上并未采用加压的措施来提高二氧化硫的产率,其理由是

                                     

2、在硫酸工业制法中,下列生产操作与说明生产操作的主要原因二者都是正确的是(  )

A、硫铁矿燃烧前需要粉碎,因为大块的硫铁矿不能在空气中燃烧

B、从沸腾炉出来的炉气需净化,因为炉气中二氧化硫会与杂质反应

C、二氧化硫氧化为三氧化硫时需使用催化剂,这样可以提高二氧化硫的转化率

D、三氧化硫用98.3%的浓硫酸吸收,目的是防止形成酸雾,以便使三氧化硫吸收完全

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