(24分)下图所示为实验室常用的实验装置: (1)写出下列仪器名称:a;b。

题型:实验题

问题:

(24分)下图所示为实验室常用的实验装置:

(1)写出下列仪器名称:a       ;b       。

(2)实验室用高锰酸钾制取氧气时,应选择的发生装置是    (填装置的字母代号),化学方程式是    ,用双氧水制取氧气的化学方程式为    。

(3)实验室用锌和稀硫酸反应制取氢气的化学方程式是    ,若将E装置中收集的氢气排出,应从   (填c或d)口通入蒸馏水。

(4)装置C相对于装置B在操作方面的优势为    。

A.可以随时加液      B.可以控制反应速率    C.可以控制反应发生与停止

同学们对美术组的环保石头纸(主要成分为碳酸钙,加入适量聚乙烯和少量胶合剂)展开探究:

[拓展实验一] 探究影响石头纸与盐酸反应快慢的因素

(5)甲、乙两同学设计实验如下:

 
实验过程
现象试管①、②、③中产生气泡快慢的顺序为:

①>②>③。

分析结论Ⅰ 碳酸钙与稀盐酸反应的化学方程式为      

Ⅱ 对比甲同学实验①②可知,       ,化学反应的速度越快;

Ⅲ 对比甲同学实验  (填实验序号)可知,反应物的接触面积越大,反应速率越

Ⅳ 乙同学的实验中,数据记录纸上应该连续记录的实验数据是    和   

[拓展实验二] 测定石头纸中碳酸钙的质量分数

(6)甲组同学的方法是:(同温同压下,不同气体混合后体积等于混合前各气体体积之和。)

将样品与稀盐酸反应,测定反应后生成CO2的体积,再换算为质量,最后根据CO2的质量求出样品中碳酸钙的质量。下图(Ⅰ)为石头纸与稀盐酸反应的装置,图(Ⅱ)用于测量CO2的体积。

① 连接仪器,夹紧弹簧夹,向a中加入一定量的水,如果a、b中有稳定的高度差,说明:装置(I)气密性   (选填“良好”或“漏气”)

② 图(Ⅱ)装置中油层的作用是_  

③ 反应停止后,  (填序号)可使反应前后油层上方气体压强和外界大气压相同,此时排出水的体积即为生成二氧化碳的体积。

A. 水平移动量气管         B.上下移动量气管       C. 封闭量气管

(7) 乙组同学的实验方法是:均匀称取四份样品分别和稀盐酸反应,用电子天平及有关装置,得出二氧化碳质量,实验数据记录如下表。(其他物质既不溶于水也不跟酸反应)

 第一份第二份第三份第四份
取样品质量(g)6.256.256.256.25
取稀盐酸的体积(mL)10.020.030.040.0
产生气体的质量(g)0.881.762.20m
通过对数据的分析和比较,回答下列有关问题:

① 在第1份样品的实验中,    完全反应了。

② m为    

③ 石头纸样品中碳酸钙的质量分数是多少?(请写出计算过程,4分)    

④ 请在坐标图中画出在6.25 g样品中加入稀盐酸的体积与产生气体质量的关系图。    

考点:实验室制取和收集气体的思路二氧化碳的性质实验化学实验数据的分析家庭小实验、趣味实验
题型:实验题
在△ABC中,O为BC的中点,M,N分别在AB,AC上,且AM=6,MB=4,AN=4,NC=3,∠MON=90°,求
AB
AC
的值.
题型:实验题

患者经来或先或后,量少色淡,头晕耳鸣,腰腿酸软,小便频数。宜首选

A.归脾汤

B.八珍汤

C.六味地黄汤

D.固阴煎

E.保阴煎

题型:实验题

(8分)

(1)下列关于氢氧化钡性质的描述中,属于碱的共同性质的是                    

A.能使紫色石蕊溶液变蓝色

B.能与盐酸反应生成水

C.能与Na2SO4溶液反应生成BaSO4沉淀

D.能与CO2反应生成水(2) 氢氧化钡与其它不同的碱表现出一些共同的性质,这是因为碱溶液中都含有   (用符号表示)。

(3)根据下图可以看出酸与碱发生中和反应的微观本质是                                 

 

(4)请写出氢氧化钡与下列物质反应的化学方程式:

①与CO2反应:                                                       

②与CuCl2溶液反应:                                                 

题型:实验题

In some countries where racial prejudice is acute, violence has so come to be taken for granted as a means of solving differences that it is not even questioned. There are countries where the white man imposes his rule by brute force; there are countries where the black man protests by setting fire to cities. Important people on both sides, who would in other respects appear to be reasonable men, get up and calmly argue in favor of violence--- as if it were a legitimate solution, like any other. What is really frightening, what really fills you with despair, is the realization that when it comes to the crunch(关键时刻), we have made no actual progress at all. We may wear collars and ties instead of war-paint, but our instinct remain basically unchanged. The whole of the recorded history of the human race, that tedious documentation of violence, has taught us absolutely nothing. We have still not learned that violence never solves a problem but makes it even acute. The sheer horror, the bloodshed(流血), the suffering mean nothing. No solution ever comes to light the morning after when we dismally contemplate the smoking ruins and wonder what hit us.

The truly reasonable men who know where the solutions lie are finding it harder and harder to get a hearing. They are despised, mistrusted and even persuaded by their own kind because they advocate such apparently outrageous things as law enforcement(执行). If half the energy that goes into violent acts were put to good use, if our efforts were directed at cleaning up the slums and ghettos, at improving living standards and providing education and employment for all, we would have gone a long way to arriving at a solution. Our strength is sapped by having to mop up the mess that violence leaves in its wake. In a well-directed effort, it would not be impossible to fulfill the ideals of a stable social programme. The benefits that can be derived from constructive solutions are everywhere apparent in the world around us. Genuine and lasting solutions are always possible, providing we work within the framework of the law.

72. What is the best title for this passage?

A. Advocating Violence.            

B. Violence Can Do Nothing to Diminish Race Prejudice

C. Violence as a Legitimate Solution  

D. Violence: The Instinct of Human Race

73. Recorded history has taught us __________.

A. violence never solves anything   B. nothing

C. the bloodshed means nothing     D. everything

74. It can be inferred that truly reasonable men ________.

A. can’t get a hearing   B. are looked down upon 

C. are persecuted      D. have difficulty in advocating law enforcement

75. According to the author, the best way to solve race prejudice is ________.

A. law enforcement   B. knowledge  C. nonviolence   D. mopping up the violent mess

题型:实验题

对于已经完成销售手续并确认收入,若月末购货人未提走所购商品,企业应该将该商品计入( )。

A.在途商品

B.代管商品备查簿

C.发出商品

D.库存商品

更多题库