在Fe、S2-、H+、Na+、S、Fe2+等物质或粒子中：（1）只能被氧化，不_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题填空题

在Fe、S^2-、H⁺、Na⁺、S、Fe²⁺等物质或粒子中：

（1）只能被氧化，不能被还原的是______；

（2）只能被还原，不能被氧化的是______；

（3）既能被氧化，又能被还原的是______．

答案

Fe的化合价是0价，最低价态，只有还原性，只能被氧化；

S^2-的化合价是-2价，最低价态，只有还原性，只能被氧化；

H⁺的化合价是+1价，最高价态，只有氧化性，只能被还原；

Na⁺的化合价是+1价，最高价态，只有氧化性，只能被还原；

S的化合价是0价，中间价态，既有氧化性又有还原性，既能被氧化又能被还原；

Fe²⁺的化合价是+2价，中间价态，既有氧化性又有还原性，既能被氧化又能被还原；

故答案为：（1）只能被氧化，不能被还原的是Fe，Cu，S^2-，故答案为：Fe、S^2-；

（2）只能被还原，不能被氧化的是H⁺、Na⁺，故答案为：H⁺、Na⁺；

（3）既能被氧化，又能被还原的是S、Fe²⁺，故答案为：S、Fe²⁺．

多项选择题

寿命期不等的互斥方案比选方法有（）。

A.最小公倍数法

B.研究期法

C.年值法

D.增量内部收益率法

E.内部收益率法

单项选择题

The first and most important agents of socialization are the people who care for infants. In the earliest months, messages from nurturers constitute the child’s basic understanding of the world around it. This is the infant’s first introduction to the language that shapes perception and elicits emotion.
Another powerful source of information and socialization is the friendship of peers. Peers are equals that one can deal with on the same level as oneself, whereas parents are superiors. The heavy emotional overlay of family relationships makes some kinds of learning difficult.
Much formal socialization is placed in the hands of professionals. Teachers from kindergarten on are specifically designated agents of socialization. Ideally, a teacher is one who has both knowledge and the skills to present it. During the course of teaching their subjects, classroom instructors provide role models and attempt to convey the excitement of learning itself.
In earlier times, parents, friends and teachers would comprise the list of primary childhood socializers. Children’s books, comics and magazines might also have been mentioned as sources of information on norms and role models. Today one must add three powerful indirect or non-personal socialization agents: radio, movies and television. Many people learn about politics, form a vision of well-being, and develop attitudes towards others from what they see on the screen and hear through the speakers.

______ are the first formal socialization agents.

A．Infant nurturers

B．Family members

C．Group peers

D．School teachers