实验室为标定一种烧碱样品的物质的量浓度,称取该烧碱样品4.0g配成1L溶液,取出

题型:选择题

问题:

实验室为标定一种烧碱样品的物质的量浓度,称取该烧碱样品4.0g配成1L溶液,取出20.00mL置于锥形瓶中,用0.10 mol·L-1 HCl标准溶液滴定,恰好完全中和时消耗标准盐酸19.00mL,若烧碱中只含有一种杂质,则不可能是( )

A.NaCl

B.Ca(OH)2

C.Na2CO3

D.NaHCO3

考点:盐水解的影响因素水解方程式盐类水解判断溶液酸碱性或比较溶液pH值的大小盐类水解的定义
题型:选择题

阅读理解。

     Once upon a time, there was a farmer. He didn't have a lot of money, so he used an old horse

to plow(耕)his field instead of a tractor(拖拉机).

     One afternoon, while working in the field, the horse died. Everyone in the village said, "Oh, what

a terrible thing!" The farmer just said, "We'll see." He was such a good person that the villagers got

together and bought him a new horse as a gift.

     Then many people said, "What a lucky man!" And the farmer replied, "We'll see." 

     A few days later, the new horse jumped over the wall and ran away. Everyone in the village said,

"What a poor man!" 

     The farmer smiled and said. "We'11 see." But finally, the horse found his way home, and everyone

said, "What a fortunate man!" The farmer said, "We'll see."

     Later in the year, the farmer's young boy went out, riding on the horse. He fell off the horse and

broke his leg. Everyone in the village said, "What a poor boy!" The farmer said, "We'll see." 

     Two days later, the army came into the village to ask people to be soldiers. When they saw that

the farmer's son had a broken leg, they decided not to ask him to join the army.

     Everyone said, "What a lucky young man!" The farmer smiled again and said, "We'll see."

1. The farmer used a horse to plow the field because _____.

A. the horse was his best friend

B. the horse was very young and strong

C. he was too poor to afford a tractor

D. the field was only suitable for horses 

2. After the horse died, the farmer was _____ when he heard the villagers' words. 

A. happy

B. calm

C. afraid

D. angry 

3. When the farmer's new horse ran away, the villagers _____.

A. gave the farmer another horse

B. liked the farmer's attitude (态度)

C. hated the farmer

D. felt sorry about it  

4. From the passage we learn that _____.

A. we should do things when we can

B. we should be sad when we are in trouble

C. we should not believe what other people say

D. if we are positive, all situations (境遇) are gifts

题型:选择题
选出不属于同一类的词。

( ) 1. A. dish       
( ) 2. A. bathroom   
( ) 3. A. refrigerator
( ) 4. A. make       
( ) 5. A. bathtub    
( ) 6. A. vegetable  
( ) 7. A. mine       
( ) 8. A. carrot     

B. wash       
B. living room  
B. stove      
B. lunch      
B. lamp       
B. make       
B. your       
B. onion      
C. bed      
C. classroom
C. dry      
C. breakfast
C. dirty    
C. cook     
C. yours    
C. door
题型:选择题

《南京临时政府组织大纲》规定的行政机关是()。

A.临时大总统

B.副总统

C.行政各部

D.参议院

E.检察院

题型:选择题

风管支架不能设置在风口、阀门、检查孔及自控机构处,也不得直接吊在法兰上。

题型:选择题

大黄治疗氮质血症的作用机理()

A、使肠内氨基酸吸收减少

B、抑制体蛋白分解

C、抑制尿素和肌酐排泄

D、血中必须氨基酸利用增加

E、促进肾代偿性肥大

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