In view of the basic chemical behavior of raw materials used in mercury cell

the factors in relationship with explosion is as follows: The self-dissolution of zinc in alkaline solutions; the unstable characteristics of residual mercurous nitrate in the mercuric oxide; and the ratio of positive and negative active materials.Three explosion-factors have been revealed:（a） The undecomposed mercurous nitrate is remained in mercuric oxide.（b） The equivalent quantity of zinc powder is over that of mercuric oxide.（c） The poor amalgamation of zinc powder.The experimental results showing that all the above three factors may resulted in the quick elevation of the pressure in the cell which caused the explosion of the cell.