问题 填空题

(14分)Q、R、X、Y、Z五种元素的原子序数依次递增。已知:

①Z的原子序数为29,其余的均为短周期主族元素;

②Y原子价电子(外围电子)排布为msnmpn

③R原子核外L层电子数为奇数;

④Q、X原子p轨道的电子数分别为2和4。请回答下列问题:

(1)在[Z(NH3)4]2离子中,Z2的空轨道接受NH3分子提供的________形成配位键。

(2)Q与Y形成的最简单气态氢化物分别为甲、乙,下列判断正确的是________。

a.稳定性:甲>乙,沸点:甲>乙                    b.稳定性:甲>乙,沸点:甲<乙

c.稳定性:甲<乙,沸点:甲<乙                    d.稳定性:甲<乙,沸点:甲>乙

(3)R元素的气态氢化物丙的沸点比同主族下一周期的元素气态氢化物高很多,原因是:________________________________________________;丙的空间构型________,杂化轨道类型________。

(4)Q、R、X三种元素的第一电离能数值由小至大的顺序为________(用元素符号作答)。

(5)Q的一种氢化物相对分子质量为26,其分子中σ键与π键键数之比为________。

答案

(1)孤电子对 (2)b   (3) 因丙中含有氢键 三角锥形    SP3

4)C< O< N  (5) 3:2 

原子序数是29的元素为铜,Z是Cu。Q、X原子p轨道的电子数分别为2和4,所以Q是C元素,X是O元素。Q、R、X、Y、Z五种元素的原子序数依次递增,因此R是氮元素。

Y原子价电子(外围电子)排布为msnmpn,则n=2,即Y是第ⅣA元素,所以是Si。

(1)配位键的形成必须有提供孤电子对的配体和接受孤电子对的空轨道。

(2)Q与Y形成的最简单气态氢化物分别为CH4和SiH4,碳的非金属性强于硅的,所以稳定性前者强,二者形成的晶体是分子晶体,后者的沸点高。

(3)氨气中含有氢键,所以沸点高。根据价层电子对互斥理论可知氨气中中心原子的有1对孤电子对,所以构型是三角锥形,采用sp3杂化。

(4)非金属性越强,第一电离能越大。

(5)Q的一种氢化物相对分子质量为26,所以是乙炔,乙炔中含有碳碳三键,三键是由2个π键和1个σ键构成的,C-H之间的单键是σ键,所以答案是3:2。

单项选择题
阅读理解

A famous study was done in a school by a professor from a university.At the start of the school year,the teachers were given the names of five children.They were told that these five were the most excellent students in the class.But the fact was that these students were only average,and they were not the best students at all.Well,guess what? At the end of the year,all the five average students scored among the highest in the class.

What made these average students change so much to become top students? The only difference was the change in their teachers’ attitude.Because the teachers believed that these five kids were the top students,they expected more from them.And so these five average students began to believe and expect more from themselves.So they worked harder to do as well as they could.

Do you know? If you expect the best from people,they’ll usually want to give you their best.A great leader said,“Treat a person just how he appears to be on the outside,and you’ll make him even worse.But treat a person like he’s already a success,and you’ll help make him the best he can be.”

Like the true story of 7-year-old Johnny,his teacher got so angry with him that one day she said,“Johnny,you’re the naughtiest(最顽皮的) boy in this class.I’m sure you’ll never change.”The next year Johnny had a new teacher.And on the first day of class,she met with Johnny after school and said,“Johnny,I’ve heard a lot about you! But do you know that I don’t believe a word of it.”And every day after that,this new teacher treated Johnny as if he was one of the smartest students even when Johnny did naughty things.Later on,Johnny became a school leader.Because that’s the power of our belief and attitude toward children.

1.The professor started his research by ________.

A.telling the five students to work harder than ever before

B.teaching the five children himself

C.telling the teacher the five students were the best in the class

D.asking the five children to find a new teacher

2.The five average students became top students mainly because of ________.

A.the professor’s study     B.the change in the professor’s attitude

C.the teachers’ hard work   D.the change in the teachers’ attitude

3.Why did the writer tell us the story of 7-year-old Johnny?

A.To show the importance of encouragement.

B.To show that the boy was clever enough.

C.To let us know the famous boy.

D.To let us know how good his new teacher was.

4.According to the story,we can learn that ________.

A.the research began at the end of the school year

B.the students scored highest only because they worked hard

C.if you expect the most from people,you’ll get the least

D.little Johnny liked his new teacher very much

5.What does the passage mainly tell us?

A.If you want to get more,you should have new teachers.

B.Attitude and belief can change a person.

C.A professor’s study can help you score highest.

D.Only teachers can make you a top student.