问题 问答题 简答题

请简单讨论表面活性剂在稀溶液中对表面张力的影响情况。

答案

参考答案:

在稀溶液中,表面活性剂按极性相似规则绨合分子、溶液中的表面活性剂单个分子和吸附层中表面活性剂分子三者之间的动态平衡,表面活性剂分子不能产铺于液面,而是倾斜于液面,因此对表面张力的影响相对减小。

单项选择题
阅读理解

阅读理解。

     认真阅读下列短文,并根据所读内容在文章后表格中的空格里填入最恰当的单词。注意:每空格

1个单词。

     A long story about people is usually called a novel. It can be about any kind of man, woman, or child.

It can be about kings, or Chicago newsboys, or housewives. The French writer, Victor Hugo, wrote his

novel Les Miserables about a poor man who stole a loaf of bread. The American writer, Ernest Hemingway,

wrote A Farewell to Arms about a young American with the Italian Army in World War One.

     A novel can tell the story of any kind of action, over any period of time. The modern Irish writer, James,

Joyce, covers less than twenty- four hours in Ulysses. Yet, Joyce takes a thousand pages to tell all that

happens from the time one man gets up in the morning until he goes to bed early the next morning. A

German writer, Herman Hesse, uses only one hundred and fifty pages in his novel Demian to cover a boy's

life from the age of ten until he becomes a young man.

     A novel does not just tell the things that people do. It also tells why they do them. The Badge of Courage,

by the American novelist, Stephen Crane, tells about a young soldier in the War between the states who runs

away the first time he is in battle. The book shows why he acted as he did. It describes his mental suffering

until he overcomes his fears. People buy novels because they enjoy reading about other people. The novel

satisfies the human desire to know and understand our fellow creatures.