(1)①三周期ⅥA族 ..........................................................(1分)
②
...........................................................(1分)
③
............................................................(1分)
….(2分)
④
............................................................................(1分)
(2)Cl ...........................................................................(1分)
bde ...........................................................................(2分)
(3)NaOH ..........................................................................(1分)
(4)①BaSO 4..........................................................................(1分)
BaCl 2+SO 2+H 2O 2=BaSO 4↓+2HCl(或Ba 2++SO 2+H 2O 2= BaSO 4↓+2H +)....(2分)
②1:2 ..........................................................................(2分)
略