题干

盛有饱和氢氧化钠溶液的烧杯在空气中放置一段较长时间,该溶液中的(   )

A:氢氧化钠的质量保持不变

B:氢氧化钠的质量变小

C:氢氧化钠的质量分数增大

D:氢氧化钠的质量分数保持不变

上一题 下一题 0.0难度 选择题 更新时间:2018-11-12 02:47:16

答案(点此获取答案解析)

B

同类题1

阅读下面的短文,掌握其大意,然后从每小题所给的A、B、C、D四个选项中,选出一个最佳选项。

    When I was a teenager growing up in France, I wanted to leave school and have my own life. The only way I could 1 this was to work in the local paper factory in my town, or get married. I was very nervous when I told my 2  I wanted to leave school. I thought he would say, “No! You are going to college.”I was very 3 when he said, “OK. Let's go to the paper factory.”

    Two days later, he took me to the factory. I imagined everyone to be friends,  4   together and having fun. I even imagined there would be music and singing. I  5  I had watched too many movies as a teenager.

    When we arrived at the factory gate, my father spoke to the guard(门卫) and one minute later we were  6. I walked around the factory looking at the building, the workers and listening to the noise. It was 7. I ran back to my father and said, “I want to go home.”

    He asked me, “What do you think of the factory?”

  “Too bad,” I answered.

  “And marriage is even  8!”he said.

     I went back to school the next day thinking about studying hard  9I could get into a good college. I enjoyed studying English so I decided to major in(主修) languages at college.   

     Thanks to my father and our  10 to the paper factory, I now work at the United Nations and my father is very proud of me. I married a very good man and my life is much better than it would have been working in the factory!

同类题2

以下为康熙时期地方增丁统计表,其中1676年福建莆田未做统计的原因可能是
年代 
福建莆田
直隶宝坻
湖北川汗
康熙十五年(1676)
 
192丁
0丁
康熙二十五年(1686)
88丁
22丁
24丁
康熙三十年(1691)
58丁
10丁
14丁