A:Na、Al、Fe金属单质在一定条件下与水反应都生成H2和对应的碱
B:H2O2、Na202、SO2都具有漂白性且漂白原理相同
C:饱和Na2C03溶液中通入CO2溶液会变浑浊
D:可用石灰水吸收尾气中的S02气体
The maths problem is very easy, so I can work it out ________.
—It's difficult for me ________ there are few new words in it.