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问题 选择题

据报道：爆炸性的高能N5+阳离子（氮元素的原子序数为7）被美国加州空军基地研究高能材料的化学家合成，关于N5+的说法正确的是：（　　）

A．该粒子的质子数为34

B．该粒子由5个氮分子构成

C．该粒子的电子数为34

D．它是一种由5个氮原子构成的单质分子

答案

答案：C

题目分析：A、N的质子数为7，微粒中含有5个氮原子，该粒子的质子数为35；

B、该微粒为阳离子；

C、阳离子的电子数等于质子数减去电荷数，为34；

D、由信息可知爆炸性的高能N5+为阳离子。

点评：本题属于信息习题，学生应抓住信息中爆炸性的高能N5+阳离子是解答本题的关键，并注意结合所学知识来解答，注重基础，难度不大。

单项选择题

因为（），电池的更换应在NC的电源接通状态下进行。

A.不这样存储器的绝对值位置会丢失

B.保护显示器

C.保护电路

D.保护操作者
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单项选择题

A


A jobless man wanted very much to have the position of "office boy" at Microsoft. The HR manager interviewed him and then watched him cleaning the floor as a test. "You have passed the test," he said. "Give me your e-mail address and I’ll send you the form to fill in and the date when you may start. " The man replied, "But I don’t have a computer, neither an e-mail. " "I’m sorry," said the HR manager. "If you don’t have an e-mail, that means you are not living. And anyone who isn’t living cannot have the job. "
The man left with no hope at all. He didn’t know what to do with only $ 10 in his pocket. He thought and thought. Then he went to the supermarket and bought 10 kilos of tomatoes. He sold the tomatoes from door to door. In less than two hours, he had 20 dollars. He repeated the operation three times, and started to go early every day, and returned home late. Shortly, he bought a cart, then a truck, then he had his own fleet of delivery vehicles(运货车队). Five years later, the man was one of the biggest food retailers (零售商)in the US.
One day, one of his friends asked him for his e-mail. He said, "I haven’t got one. " His friend couldn’t believe his ears. "Can you imagine what you could have been if you had an e-mail" The man thought for a while and replied, "Yes, I’d be an office boy at Microsoft!\

Why could the man become one of the biggest food retailers in the US

A．Because he had many friends to help him.

B．Because he was smart and worked very hard.

C．Because he had his own fleet of delivery vehicles.

D．Because he wanted to show Microsoft he was livin
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