A.HF、HCl、HBr、HI B.HI、HBr、HCl、HF C.HCl、HBr、HI、HF D.HF、HI、HBr、HCl
A.1 B.2 C.3 D.4
A.3d34s2 B.3d5 C.3s23p63d5 D.3s23p63d34s2