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问题 选择题

甲醛是装修材料中常见的污染物．其分子结构如图所示，下列说法正确的是（　　）

A．甲醛是有机物

B．甲醛的相对分子质量为30g

C．甲醛由一个碳原子、2个氢原子和1个氧原子构成

D．甲醛中碳、氢、氧三种元素的质量比为1：2：1

答案

答案：A

题目分析：A、由甲醛的分子结构图可知，1个甲醛分子是由1个碳原子、2个氢原子和1个氧原子构成的，其化学式为：CH2O，甲醛是含有碳元素的化合物，属于有机物，故选项说法正确．

B、相对分子质量单位是“1”，不是“克”，常常省略不写，故选项说法错误．

C、甲醛是由甲醛分子构成的，1个甲醛分子是由一个碳原子、2个氢原子和1个氧原子构成的，故选项说法错误．

D、甲醛中碳、氢、氧三种元素的质量比为（12×1）：（1×2）：（16×1）≠1：2：1，故选项说法错误．

故选A．

点评：本题难度不大，考查同学们结合新信息、灵活运用化学式的含义与有关计算进行分析问题、解决问题的能力．

单项选择题 A1/A2型题

下列关于军团菌的叙述，正确的是（）。

A.革兰染色阴性球菌

B.革兰染色阳性球菌

C.革兰染色阴性杆菌

D.革兰染色阳性杆菌

E.具有荚膜结构
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单项选择题

When we think of leadership, we often think of strength and power. But what are these really, and how do they operate
Leadership today is not about forcing others to do things. If this is even possible, it is short term, and tends to backfire. If you order someone to do something against their will, they may do it because they feel they must, but the anger they feel will do more harm in the long term. They will also experience fear.
Fear causes the thinking brain to shut down, making the person unable to function at his or her best. If they associate you with this emotion of fear, they will become less functional around you, and you will have succeeded in not only shooting yourself in the foot, but possibly making a very good employee or partner unable to perform effectively. Fear has no place in leadership.
The way we influence people in a lasting way is by our own character, and our understanding and use of emotion. We can order someone to do something, which may be part of the workday; or we can employ them at the emotional level, so they become fully devoted to the projects and provide some of their own motivation. Today’s workplace is all about relationships as a human being as well as a worker. Everyone produces just a bit more for someone they like. Leaders understand the way things work. They know the paycheck is not the single most motivating factor in the work life of most people.
The true strength of leadership is an inner strength that comes from the confidence of emotional intelligence—knowing your own emotions, and how to handle them, and those of others. Developing your emotional intelligence is the single best thing you can do if you want to develop your relationships with people around you, which is the key to the leadership skills.

An employee may have a feeling of fear in the workplace when ______.

A．he is forced to do things

B．be cannot work at his best

C．he feels his brain shut down

D．he thinks his work is too heavy
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