久置的氢氧化钠中常含有______杂质.检验是否含有此杂质时常用的试剂是____

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问题:

久置的氢氧化钠中常含有______杂质.检验是否含有此杂质时常用的试剂是______,其反应的化学方程式为______,除去此杂质常用的试剂是______,其反应的化学方程式为______.

考点:化学反应方程式的书写文字表达式碱的性质物质的变质物质的保存
题型:填空题

Joyce was born in a poor family. Next Friday would be her mother’s birthday. Joyce wanted to buy something for her mother, but she had no money. As an 8-year-old girl, she couldn’t do part-time jobs. What could she do to make enough money for her mother’s birthday present?

Suddenly she had an idea. Usually, she would go straight to school, but this morning, she didn’t. She walked along the streets, picking up cardboard(纸板), plastic(塑料)bottles and cans(易拉罐). When it was time for school, she hid them in the backyard and ran to school as quickly as possible.

Eight days later, she decided to sell all the things she had collected because the next day was her mother’s birthday. She had to sell them and buy a birthday present for her mother. In the shop, she bought a beautiful hair pin for her mother.

When her mother got the present, she said with tears in her eyes,“This is the best present I’ve ever received.”

小题1:How old was Joyce?

A. Seven.           B. Eight.        C. Nine.         

小题2:Why couldn’t Joyce buy a present for her mother at first?

A. Because she had no money.

B. Because she didn’t know what her mother liked.

C. Because she didn’t love her mother at all.

小题3:What was Joyce’s idea?

A. Doing part-time jobs.   

B. Collecting waste things and selling them.

C. Asking her best friend for help.

小题4:How long did Joyce collect the waste things?

A. A week.      B. A month.    C. More than a week.

小题5: How did Joyce’s mother feel when she got the present?

A. Very sad.      B. Very happy and moved.     C. Very surprised.

题型:填空题

欢欢家、乐乐家和电影院在同一条笔直的马路上,欢欢家离电影院2千米,乐乐家离电影院800米,欢欢家和乐乐家最远可能相距多少米?最近呢?

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输卵管癌的叙述正确的是()

A.一般为继发性

B.多见于绝经后妇女

C.有异常 * * 排液

D.常伴下腹痛

E.常有慢性附件炎病史

题型:填空题

客户关系管理的作用:()、()、()、()

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承购包销公债的主体有()

A.广大中小企业

B.专业银行

C.金融集团

D.个人

E.行政部门

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