某同学对下列四个实验都设计了两种方案。其中，两个方案理论上均可行、且第二方案比第

发布时间：2017-07-01 16:22 │ 来源：www.tikuol.com

题型：选择题

问题：

某同学对下列四个实验都设计了两种方案。其中，两个方案理论上均可行、且第二方案比第一方案更方便合理的是（）

	实验目的	第一方案	第二方案
A	除去氯化钙固体中少量氯化铵	与熟石灰混合加热	直接加热
B	清洗热水瓶中的水垢	用食醋洗涤	用洗洁精洗涤
C	检验亚硫酸钠是否被氧化	滴入Ba(OH)₂溶液	滴入盐酸酸化的BaCl₂溶液
D	区分黄铜（铜锌合金）和黄金	测量密度	加盐酸，看气泡

考点：物质的分离离子的检验粗盐的提纯

题型：选择题

检查油泵的安全阀，动力缸是否良好，接上带开关的压力表，打开开关，转动方向盘到尽头，压力表读数达不到规定值，关闭开关后压力表读数也达不到规定值，甲说油泵或安全阀有故障。乙说动力缸或分配阀有故障。则（）。

A.甲正确。

B.乙正确。

C.两人均正确。

D.两人均不正确。

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题型：选择题

     Hurricane Katrina was one of the most devastating (毁灭性的) tragedies in American history. Since
our   1   was given prominent media exposure, we   2 thousands of calls per day.
I spoke with countless victims who were trying to locate family members lost in the flood. They all
needed   3 with housing, food and clothing. It took weeks   4   federal assistance was available to the
majority. Some received none.
        5 we were there to help, the trauma(心灵创伤) made some callers rude. Some were    6  . Some
were suicidal(有自杀倾向的). It was hard to stay   7   and encouraging. Just at that time, I got a call
from Brenda.
     Brenda was a single woman   8   her early fifties with no children. She was all alone and had been
living in a crowded   9   in Houston for the past month. She said, "I've heard that my house was still
   10   and at this point, the hardest part of all of this, though, is seeing the   11   suffer. The young tend
to recover easily,   12   many of the elderly have no other resources."
     Brenda was hit hard but her heart still overflowed with   13   for others.
     "I know that recovery lies ahead," she continued. "I   14   that if we were the ones chosen to endure
(忍受) this   15   , then God will give us the grace to endure. The   16   of our city has given birth to a
spirit of unity."
     "My hope isn't   17   on my circumstances," she continued. "My hope is based on my 18   to hope.
Hope is a choice."
     The only thing Brenda could   19   was her attitude. She made a decision to thrive(茁壮成长), not
just   20   .

( )1. A. airline
( )2. A. devoted
( )3. A. acceptance
( )4. A. when
( )5. A. Even though
( )6. A. impatient
( )7. A. unconcerned
( )8. A. in
( )9. A. street
( )10. A. underworld
( )11. A. wounded
( )12. A. and
( )13. A. instruction
( )14. A. doubt
( )15. A. friendship
( )16. A. population
( )17. A. based
( )18. A. decision
( )19. A. appear
( )20. A. leave

B. hotline
B. dealt
B. attendance
B. while
B. As though
B. patient
B. angry
B. at
B. road
B. underground
B. elderly
B. or
B. description
B. wonder
B. scholarship
B. development
B. lay
B. opinion
B. change
B. accept

C. office
C. handled
C. appearance
C. before
C. Therefore
C. moved
C. positive
C. for
C. church
C. undersea
C. young
C. but
C. compassion
C. wander
C. membership
C. destruction
C. seated
C. idea
C. experience
C. defeat

D. website
D. offered
D. assistance
D. after
D. However
D. delighted
D. pessimistic
D. by
D. shelter
D. underwater
D. poor
D. so
D. addiction
D. believe
D. hardship
D. story
D. affected
D. mind
D. solve
D. survive

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题型：选择题

某化学活动小组以“酸碱盐的性质”为主题，进行探究学习，请你做为该小组成员协助解决下列问题：（1）小羽同学说：“酸溶液呈酸性，碱溶液呈碱性，则盐溶液一定呈中性”。你认为这种推理（填“正确”或“不正确”），请举例说明。

（2）小弘同学从某农田里取回一份土壤样品，请你用两种不同的方法帮小弘测出该土壤样品液体的酸碱性（只写出所用试剂的名称即可） ① ② ，

如果检测的结果呈酸性，那么要改良此土壤，应该向农田里施加。

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题型：选择题

禽大肠杆菌病剖检的病变特征是（）。

A.纤维素性心包炎、肝周炎

B.肠黏膜出血

C.脾脏肿大

D.肺出血

E.盲肠栓子

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题型：选择题

系膜增生性肾小球肾炎电镜下可见（）

A．上皮细胞足突消失

B．上皮下驼峰样沉积物

C．系膜区沉积物

D．内皮下、致密层和上皮下沉积物

E．上皮下沉积物伴基膜增厚

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