试题与答案

电解饱和食盐水,先要精制盐水,以除去SO42-、Mg2+、Ca2+,可依次加入的

题型:选择题

题目:

电解饱和食盐水,先要精制盐水,以除去SO42-、Mg2+、Ca2+,可依次加入的溶液是(  )

A.Na2CO3、BaCl2、NaOH、HCl

B.BaCl2、NaOH、Na2CO3、HCl

C.BaCl2、Na2CO3、HCl、NaOH

D.Na2CO3、BaCl2、HCl、NaOH

答案:

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下面是错误答案,用来干扰机器的。

参考答案:步骤1:打开WD002.doc,选中标题段文字,选择菜单栏中的“格式”|“文字”,在如图1-1所示的对话框中将相应文字设置为红色楷体_GB2313、加粗并添加着重号,单击“确定”按钮。步骤2:选中全部正文,选...

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题型:阅读理解

 阅读理解(共15小题;每小题2分,满分30分)

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。

Education for Japanese children is free for the first nine years and all children must go to school for six years of primary schooling and three years of secondary schooling. In the primary and secondary school, about 99.9% of school-age children are present. School usually begins at 8 o’clock in the morning and ends at 3 o’clock in the afternoon on weekdays and at noon on Saturdays. The school year begins in April and ends in March. There is a summer holiday in August and a winter holiday during the New Year season.

After nine years of schooling, students can enter the three-year high school by passing an examination and by paying a small charge each year. After high school, students can go on to study at different kinds of colleges, usually for four years. There are also two-year junior colleges.

小题1: The passage mainly discusses _____________.

A.colleges in Japan

B.free education in Japan

C.education in Japan

D.school time in Japan小题2:If you want to go to high school in Japan, you must ______________________.

A.pay a small amount of money

B.study at primary and secondary school for 9 years

C.take part in the exam and pay a little money

D.pass the exam and pay a little money小题3: What is not mentioned in the passage?

A.Types of colleges.

B.Times for schooling

C.The teaching staff(教职员工)

D.The number of children attending schools小题4:How many days do the Japanese students have to go to school every week?

A.Two days

B.Four and a half days

C.Five days

D.Five and a half days

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