nguyen tu X co 5 electron o phan lop s , nguyen tu Y co phan lop ngoai cung la 3p3 a.viet cau hinh electron cua X,Y b.X,Y co bao nhieu lop ,goi ten cac lop ,o moi lop co bao nhieu electron ? c.trong X,Y phan lop nao co muc nang luong cao nhat ? d.X,Y thuoc loai nguyen to hoa hoc nao ? (kim loai , phi kim , khi hiem )