下图是氯化钠的形成过程示意图下列有关描述中正确的是（） A_爱下问搜题

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问题选择题

下图是氯化钠的形成过程示意图下列有关描述中正确的是（　　）

A．钠原子在反应中失去了所有的电子

B．一个氯原子如果得到一个电子就变成相对稳定结构

C．氯化钠就是两种化合物亲密地联系在一起

D．生成的氯化钠多出了一个电子

答案

A、在反应中一个钠原子失去了一个电子而变成稳定结构，故A错；

B、氯原子最外层电子数是7个，在反应中一个氯原子得到一个电子变成相对稳定结构，故B对；

C、氯化钠是一种化合物，故C错；

D、形成化合物时，得失电子总数相等，故D错；

故选B

完形填空

阅读下面短文，从短文后所给各题的四个选项（A、B、C和D）中，选出最佳选项。
Most of us lose life’s tough battles by starting an unexpected attack—when a touch of humor might well enable us to win.   the case of a young friend of mine, who was     in a traffic jam on his way to work shortly after receiving a warning about being late for the job.     there was a good reason for Sam’s being late—serious illness at home—he    that this by-now-familiar excuse wouldn’t     any longer. His boss was probably already pacing     preparing a speech to fire him.
Yes, the boss was. Sam entered the office at 9:35. The place was as     as a locker room;     was hard at work. Sam’s boss came up to him angrily. Suddenly, Sam    and stretched out his hand. “How do you do!” he said. “I’m Sam Maynard. I’m applying for a    , which, I understand, became    just 35 minutes ago. Does the     bird get the worm?”
The room exploded in laughter. The boss     a smile and walked back to his office. Sam Maynard had    his job—with the only    that could win-–a laugh.    is a most effective, yet frequently neglected ,means of handling the difficult situations in our lives. It can be used for making up differences, apologizing, criticizing and     the other fellow to do what you want     his losing face. For some jobs, it’s the only tool that can succeed. It is a way to discuss subjects so   that serious dialogue may start a quarrel.   , many believe that comedians(喜剧演员) on television are doing more today for racial and religious problems than people in any other field.

A．here and there

C．up and down

D．now and then

A．Understanding

D．Communication

B．For example

判断题

力的三大要素是力的大小、力的方向、力的作用点。( )