CaBr2+H2o=CaO+2HBr ①
2HBr+Hg=HgBr2+H2 ②
HgBr2+CaO=HgO+CaBr2 ③
2HgO=2Hg+O2 ④
四个方程式加到一起
即CaBr2+H2o+2HBr+Hg+HgBr2+CaO+2HgO=2Hg+O2+HgO+CaBr2+HgBr2+H2+CaO+2HBr
相同的消去,即：H2O+HgO=Hg+O2+H2少了个CaBr2催化剂哇？恩？是不是了呀？CaBr2应该是催化剂哇？恩，算作催化剂