【单选题】I _____ from China and Tony ______ from England. But we are good friends.
【单选题】They had to wait _____ the dog _____ out of the room. [ ]
【单选题】Spring is coming and the grass is just beginning to _____. [ ]
【单选题】Who is always the first one_____ class? [ ]
【简答题】一定量的铁粉在氯气中充分燃烧后,将所得固体完全溶于稀盐酸,制得溶液A。 (1)铁在氯气中燃烧的化学方程式是___。 (2)推测A中可能含有的金属阳离子:①只有Fe 3+ ;②只有Fe 2+ ;③____。 甲同学为探究溶液的组成,实验如下: (3)乙同学继续探究溶液A的组成。 查阅资料:l6HCl+2KMnO 4 ==2KCl+2MnCl 2 +5Cl 2 ↑+8H 2 O。 实验过程:另取少量溶...
【多选题】下列各反应中,通入的气体只能作还原剂的是( )
D.
将SO 2 气体通入酸性KMnO 4 溶液中