题目

完形填空；请先阅读下面短文，掌握其大意，然后从各个小题中所给的A,B,C，D四个选项中选出最佳选项。My dream home is very big and clean. It is near the  ( 1 ). I can watch the sea and ( 2 )  volleyball on the beach. My grandparents live ( 3 )  us in this big house. ( 4 ) room is (5) the first floor(层), too. I always chat with them and help them ( 6  ) some housework at weekends. On the ( 7 ) floor, there is a kitchen and a dinning room. All the family 8 ) will have dinner there. My bedroom, study and bathroom are on the third floor. There is a big baA、B、C、D、E是原子序数依次增大的五种短周期元素．A原子的电子层数与它的核外电子总数相同，A与C、B与D分别为同主族，B和C的最外层电子数之和与E的最外层电子数相同．A与E形成的化合物化学式为AE，其分子中含18个电子．请回答下列问题：（1）由A、B、C三种元素形成的化合物的电子式为 ，这种化合物中所含的化学键类型有 ．（2）A2B的沸点高于A2D，其原因是 ．（3）B、C、E三种元素形成一种盐，此盐中三种原子个数比为1?1?1，在25℃时，将该盐溶于水，测得溶液pH＞7，理由是 （用离子方程式表示）；将该盐溶液在空气中露置一段时间后（充分光照，不考虑水分的挥发），溶液的pH近似为7，则该过程的总反应方程式为 ．