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初中化学课本中有潮解和风化的内容,但无实验,为了加深学生对风化与潮解的认识,可补充在45分钟内可同时看到风化和潮解现象的演示实验。原理Na_2SO_4·10H_2O的离解压(饱和蒸气压)在25℃时为19.20毫米汞柱,而KOH固体在25℃时可以使1升空气中残留水分减至2×10~(-3)毫升/升,相当于0.002毫米汞柱。所以将这两种物质放入同一密闭容器中,Na_2SO_4·10H_2O将因KOH的干
There is deliquescence and weathering in junior high school chemistry textbooks, but no experiments were conducted. In order to deepen students' understanding of weathering and deliquescence, they can supplement demonstrations that can see both weathering and deliquescence within 45 minutes. Principle The dissociation pressure (saturated vapor pressure) of Na_2SO_4 · 10H_2O is 19.20 mmHg at 25 ° C, while KOH solids can reduce the residual moisture in 1 liter of air to 2 × 10 -3 ml / L at 25 ° C , Equivalent to 0.002 mm Hg. So these two substances into the same airtight container, Na_2SO_4 · 10H_2O will be due to dry KOH