(10分)配制500mL 0.5mol/L的NaOH溶液,试回答下列问题。 (1

题型:实验题

问题:

(10分)配制500mL 0.5mol/L的NaOH溶液,试回答下列问题。

(1)需要NaOH固体的质量为             

(2)某同学用托盘天平称量一个小烧杯的质量,称量前把游码放在标尺的零刻度处,天平静止时发现指针在分度盘的偏右位置,此时左边的托盘将      (填“高于”或“低于”)右边的托盘,欲使天平平衡,所进行的操作应                                                                          。假定最终称得小烧杯的质量为        (填“32.6g”或“32.61g”)。

(3)配制方法:设计了如下五个操作步骤,正确的顺序是               

①向盛有NaOH的烧杯中加入200mL蒸馏水使其溶解,并冷却至室温。

②继续往容量瓶中加蒸馏水至液面距刻度线1cm~2cm。

③将NaOH溶液沿玻璃棒注入500mL容量瓶中。

④在烧杯中加入少量的蒸馏水,小心洗涤2~3次后移入容量瓶。

⑤改用胶头滴管加蒸馏水至刻度线,加盖摇匀。

(4)某学生实际配制NaOH溶液的浓度为0.48mol/L,原因可能是(       )

A.使用滤纸称量氢氧化钠固体

B.容量瓶中原来存有少量蒸馏水

C.溶解用的烧杯未经多次洗涤

D.用胶头滴管加水定容时仰视刻度线

考点:设计实验方案及探究实验
题型:实验题

阅读理解。

     I never wanted a dog, but now I'm so glad I have one.

     About one year ago, my wife, Mary, got a little dog with a face only a mother could love. We named

her Baby.

     Baby is the kind of dog that has to grow on you. So I decided that the dog would be trained. This didn't

quite go as planned. At 15 weeks old, she was nearly made to leave the Petsmart Training School. She spent

every night lying in our bed-snoring (打鼾) so loudly that I hardly got a good night's sleep.

     Then, about six months after she arrived, I felt that something in my heart was taking place, and I was

unable to stop it. My behavior (行为方式) began to change. I began to smile at people when passing them

in a street. I returned from neighbors. I started calling my kids and, to my surprise, they started calling me.

I even tried to speak to my grandchildren over the phone once. I even was glad to listen to laughter from a

10-month-old granddaughter. The point is that I was changing.

     My wife and I both agree that it is Baby who has changed my behavior.

     Baby is now nearly one year old and almost fully grown. I have come to like the pet little by little, though

she is my wife's dog.

1. What did the man think of the dog at the beginning?

A. It wasn't very lovely.

B. It looked very beautiful.

C. It wasn't necessary to be trained.

D. It could change his life.

2. When did the man's behavior begin to change?

A. About one year ago.

B. When Baby was nearly one year old.

C. When Baby was 15 weeks old.

D. About six months after Baby arrived.

3. Which of the following is NOT mentioned about the man's change?

A. He began to smile at people.

B. He liked helping his neighbors.

C. He started calling his kids.

D. He spoke to his grandchildren over the phone.

4. What can we learn from this passage?

A. The dog has been trained very well.

B. The man has become more confident (自信的).

C. The man has become more friendly.

D. The man likes the dog better than his wife.

题型:实验题

读“我国四大地理分区图”,完成下列问题。

(1)我国四大地理分区划分的依据是[ ]

A.各区人们的生活习惯不同

B.各区的地形不同

C.各区的降水不同

D.各区的地理位置、自然和人文地理特点不同

(2)地跨①②③④四个区域的省级行政单位是[ ]

A.青海省

B.甘肃省

C.四川省

D.河南省

(3)图中①区域与②区域的分界线是____________山脉和____________山脉;③区域与④区域的分界线是____________一线。

(4)主要位于季风区的是____________地区和____________地区,而____________地区和____________地区主要位于非季风区(均填字母代号和名称)。

题型:实验题

蔬菜水果含有下列较丰富的维生素和无机盐,除了

A.维生素D
B.钾、钠
C.胡萝卜素
D.维生素C
E.维生素B2

题型:实验题

根据十二经别的分布特点,其先后顺序是:

A.出、入、离、合

B.入、出、合、离

C.离、合、出、入

D.离、入、出、合

E.离、出、入、合

题型:实验题

依据刑法,下列说法哪项是不正确的( )

A.帮助犯罪分子逃避处罚罪与徇私枉法罪的区别之一是前者发生在诉讼之前,后者发生在诉讼过程由

B.徇私舞弊少征税款罪的犯罪主体是税务机关工作人员

C.故意泄露国家秘密,情节严重的,才构成犯罪

D.徇私枉法罪和民事、行政枉法裁判罪没有本质区别

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