题目

（07年四川卷）短周期元素W、X、Y、Z 的原子序数依次增大，W与Y、X与Z 位于同一主族。W 与X 可形成共价化合物WX2。Y原子的内层电子总数是其最外层电子数的2.5 倍。 下列叙述中不正确的是（ ）  A．WX2分子中所有原子最外层都为8 电子结构  B．WX2、ZX2的化学键类型和晶体类型都相同   C．WX2是以极性键结合成的非极性分子   D．原子半径大小顺序为X ＜Y＜Z请先阅读下面短文，掌握其大意，然后用方框中所给词的适当形式填空。每个词限用一次。that, dangerous , cry , hospital , pull , run , hold , save , quick , possibleMr. Black was once a policeman. He was a kind person. He liked to have a walk in the park after breakfast. It was very cold on a winter morning. Mr. Black was walking along the street when he heard a 【1】 for help. He turned around but could see nobody. He stopped and looked here and there. At the moment, a boy 【2】 up to him. The boy was in such a hurry 【3】 he couldn't say a word except pointing towards the river. Mr. Black realized what happened and ran to the river as soon as 【4】.Both of them ran along the river and saw a girl in the water. She was【5】 a piece of wood. It was carrying her away. It was too【6】Without a word, Mr. Black took off his clothes as【7】as he could, and jumped into the river. He swam to the girl and took her back near the bank and lifted the girl up, and then the boy helped【8】her out of the water. Then they stopped a car and took the girl to the【9】.At last the girl’s life【10】,and she thanked them very much.