试题与答案

关于锅炉底部排污下列说法中错误的是()。A.应在投放除垢药后过相当长时间进行 B.各

题型:单项选择题

题目:

关于锅炉底部排污下列说法中错误的是()。

A.应在投放除垢药后过相当长时间进行

B.各种型式废气锅炉也都要底部排污

C.不允许在正常工作负荷时进行

D.每次不超过0.5min,谨防失水

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B

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题型:阅读理解

阅读再判断正误。

It’s 5:30 in the afternoon. School is over. It’s time for student to relax.

Look! Some boys are playing soccer and some are playing basketball on the playground(操场). Most girls don’t like ball games because they think they are boring. They like to do other sports, such as swimming and dancing. Look, some girls are swimming in a big swimming pool. In the gym(健身馆), Maria and her friends are dancing to the music. Some students are singing together in the classroom building. Who are they? Oh, they are some students of Class Four. They are cleaning their classroom now. After that, they can play with other students.

根据上面内容判断正误,正确的写T, 错误的写F。

小题1: After 5:30pm, the students don’t have classes.

小题2: On the playground, some boys are playing basketball and soccer.

小题3:We can’t see any students swimming in the pool now.

小题4: Some students from Class Four are singing together in the classroom.

小题5: Maria is dancing on the playground.

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题型:实验题

[2012·广东肇庆市一模](14分)I:某兴趣小组欲在绿色环保的条件下探究大气污染物SO2的性质,设计如下图实验装置。请回答:

(1)B、C、D分别用于检验SO2的漂白性、还原性和氧化性,则B中所盛试剂为        

C中反应的离子方程式为                             

(2)为了实现绿色环保的目标,某同学设计了上图A2的制取装置来代替A1装置,与A1装置相比,A2装置的优点是                                    (写两点)。

II:用氨水吸收尾气中的SO2,“吸收液”中可能含有OH-、SO32-、SO42-、HSO3-等阴离子。请回答:

(3)氨水吸收过量SO2的反应的离子方程式为                             

(4)已知亚硫酸氢盐一般易溶于水,SO2也易溶于水。现有仪器和试剂为:小烧杯、试管、玻璃棒、胶头滴管、过滤装置和滤纸;2 mol/L盐酸、2 mol/LHNO3、1 mol/LBaCl2溶液、l mol/LBa(OH)2溶液、品红溶液、蒸馏水。请设计实验证明“吸收液”中存在SO32-、HSO3-,完成下表的实验操作、预期现象和结论:

实验操作预期现象与结论
步骤1:取适量“吸收液”于小烧杯中,用胶头滴管取l mol/L BaCl2溶液向小烧杯滴加直至过量。若出现白色浑浊,则溶液中存在SO32-或 SO42-
步骤2:将小烧杯中的浊液过滤、洗涤,再用适量水把附在滤纸上的固体冲入另一小烧杯中;向冲下的固体                         

                                           

                          

                     

步骤3:                                               

                                            

                          

                      

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