题目

、、、是原子序数依次增大的短周期主族元素，原子的最外层电子数是其内层电子数的2倍，与同周期，的最外层电子数等于周期数，是地壳中含量第二的元素。下列说法正确的是（ ）A.原子半径的大小顺序： B.简单气态氢化物的热稳定性：C.的简单离子半径在同周期中最大 D.的单质与的氧化物反应可以制备的单质 Listen and fill in the blanks(听录音，完成下列对话，每空一词) (1)G：Hello, Dad! What ________ is it? B：It's 7:30 now. It's time for ________. G：What's for breakfast? B：We have got ________ and ________. (2)G：Would you like some ________? B：No, thank you. I don't like cakes. G：How about ________ then? B：Yes, please.