温度对水的离子积与溶液酸碱性的pH判据的影响

Effects of Temperature on the Ion Product of Water and pH Criteria for Aqueous Solution Acidity

讨论了温度对水的离子积Kw和溶液酸碱性的pH判据的影响,分析了容易产生的模糊认识。Kw随温度升高显著增大,使溶液呈中性的pH（中性pH=pKw/2）在高温（〉25℃）和低温区（〈25℃）分别出现小于和大于7.0的情况。

The effects of temperature on the ion product of water Kw,and the aqueous solution acidity are discussed.The fuzzy understanding that may occur on Kwand pH criteria for the aqueous solution acidity in teaching and textbooks are analyzed.Kwis reported to significantly increase with increasing temperatures,resulting in less than and greater than pH 7.0for neutral aqueous solution at temperatures greater than and less than 25℃,respectively.