问题 实验题

(12分)在花瓶中加入“鲜花保鲜剂”,能延长鲜花的寿命。下表是1L“鲜花保鲜剂”中含有的成分,阅读后回答下列问题:

成分质量(g)摩尔质量(g·mol-1
蔗糖50.0342
硫酸钾0.5174
阿司匹林0.4180
高锰酸钾0.5158
硝酸银0.2170
(1)下列“鲜花保鲜剂”的成分中,属于非电解质的是      。(填序号)

A.蔗糖      B.硫酸钾       C.高锰酸钾      D.硝酸银

(2)“鲜花保鲜剂”中K+(阿司匹林中不含K+)的物质的量浓度为        

mol·L-1(只要求写表达式,不用写出计算结果)。

(3)在配制一定物质的量浓度的溶液时,一般可分为以下几个步骤:①称量

②计算 ③溶解 ④摇匀 ⑤转移 ⑥洗涤 ⑦定容 ⑧冷却。其正确的操作顺序为                               

(4)配制上述1L “鲜花保鲜剂”所需的仪器有:1000mL容量瓶、烧杯、玻璃棒、药匙、                           。(在横线上填写所缺仪器的名称)

(5)在溶液配制过程中,下列操作对配制结果没有影响的是           

A.将药品放入容量瓶中加蒸馏水至环形刻度线

B.容量瓶在使用前未干燥,里面有少量蒸馏水

C.容量瓶在使用前刚刚配制完一定物质的量浓度的NaCl溶液而未洗净

D.定容摇匀后发现液面低于容量瓶的刻度线,但未做任何处理

答案

(12分)

(1)  A(2分)       (2)(2分) 

(3)②①③⑧⑤⑥⑦④(2分)

(4)  胶头滴管(2分); 托盘天平(2分)       (5)  BD (2分)

阅读理解
请阅读下面这篇文章,完成下面表格。
I am Jay from Zhuhai Sunshine Middle School. Recently, we carried out a survey on who we prefer to share worries with. We got different answers.
   Acording to the chart, those who would like to share their worries with their classmates and friends account for about 71%. It is mainly because they believe that if people are at the same age, they are easy to communicate and understand each other better.
  About 22% of the students said they would like to share worries with their teachers and parents. According to them, adults are rich in experience, and that they can handle their problems easily. The rest prefer to keep worries to themselves. As for them, it’s a struggle to get along well with others, some of them said they didn’t want to trust anyone.
  As far as I am concerned, I am willing to share worries with my best friends because they’re always kind and understanding. However, if I meet with some serious problems, I’ll be likely to ask my parents and teachers for help, who, I believe, have more experience to give me valuable advice.
Information Card
What is the survey we had about?
小题1:________________
How many percents of the students would like to share worries with their classmates and friends?
小题2:________________.
Why do students like to share worries with their teachers and parents?
小题3:________________.
What did the students who keep worries to themselves say?
小题4:_______________.
Why does Jay share worries with his best friend?
小题5:_______________.
 
单项选择题