The concentration of generated chlorine dioxide gas can be freely controlled, and chlorine dioxide gas can be generated promptly and stably over a long period of time. An aqueous chlorite solution, an activator that quickly adjusts the pH of the aqueous chlorite solution, an activation inhibitor that effectively reduces the action of the activator, a metal iodide, Is mixed with metal iodide in an amount of 0.4% by mass or less and 1% by mass or less of an activation inhibitor per liter of 1% by mass of chlorite aqueous solution, and chlorine dioxide gas is obtained from the liquid composition obtained. In an immediate and stable concentration. [Selection figure] None【課題】発生する二酸化塩素ガスの濃度を自在に制御可能とするとともに、二酸化塩素ガスを即効的にかつ長期に亘って安定的に発生させることができるようにする。【解決手段】亜塩素酸塩水溶液と、亜塩素酸塩水溶液のｐＨを速効的に調整する活性化剤と、活性化剤の作用を遅効的に低減させる活性化抑制剤と、金属ヨウ化物とを、１質量％の亜塩素酸塩水溶液１Ｌ当たり金属ヨウ化物を０．４質量％以下かつ活性化抑制剤を１質量％以下の割合で混合して、得られる液性組成物から二酸化塩素ガスを即効的にかつ安定的濃度で発生させる。【選択図】なし
