常温下,0.1mol/LCH3COONa溶液PH=11正确的C(CH3COO-)+C(CH3COOH)=0.1mol/L由水电力出来的C(OH-)=1.0*10-11mol/L往溶液中加入0.05mol/L的CH3COONa,PH值变大需要理由
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![常温下,0.1mol/LCH3COONa溶液PH=11正确的C(CH3COO-)+C(CH3COOH)=0.1mol/L由水电力出来的C(OH-)=1.0*10-11mol/L往溶液中加入0.05mol/L的CH3COONa,PH值变大需要理由](/uploads/image/z/12386146-58-6.jpg?t=%E5%B8%B8%E6%B8%A9%E4%B8%8B%2C0.1mol%2FLCH3COONa%E6%BA%B6%E6%B6%B2PH%3D11%E6%AD%A3%E7%A1%AE%E7%9A%84C%EF%BC%88CH3COO-%EF%BC%89%2BC%EF%BC%88CH3COOH%EF%BC%89%3D0.1mol%2FL%E7%94%B1%E6%B0%B4%E7%94%B5%E5%8A%9B%E5%87%BA%E6%9D%A5%E7%9A%84C%EF%BC%88OH-%EF%BC%89%3D1.0%2A10-11mol%2FL%E5%BE%80%E6%BA%B6%E6%B6%B2%E4%B8%AD%E5%8A%A0%E5%85%A50.05mol%2FL%E7%9A%84CH3COONa%2CPH%E5%80%BC%E5%8F%98%E5%A4%A7%E9%9C%80%E8%A6%81%E7%90%86%E7%94%B1)
常温下,0.1mol/LCH3COONa溶液PH=11正确的C(CH3COO-)+C(CH3COOH)=0.1mol/L由水电力出来的C(OH-)=1.0*10-11mol/L往溶液中加入0.05mol/L的CH3COONa,PH值变大需要理由
常温下,0.1mol/LCH3COONa溶液PH=11
正确的
C(CH3COO-)+C(CH3COOH)=0.1mol/L
由水电力出来的C(OH-)=1.0*10-11mol/L
往溶液中加入0.05mol/L的CH3COONa,PH值变大
需要理由
常温下,0.1mol/LCH3COONa溶液PH=11正确的C(CH3COO-)+C(CH3COOH)=0.1mol/L由水电力出来的C(OH-)=1.0*10-11mol/L往溶液中加入0.05mol/L的CH3COONa,PH值变大需要理由
解析:CH3COONa是强电解质,全部电离,CH3COONa=CH3COO- + Na+
CH3COO-是弱酸根离子,又水解,水解方程式:CH3COO-+H2OCH3COOH+OH-
根据物料守恒(就是特定原子守恒),这里是C原子守恒,则有:C(Na+)=C(CH3COO-)+C(CH3COOH) 而C(Na+)=0.1mol/L 则有:C(CH3COO-)+C(CH3COOH) =0.1mol/L
又因为CH3COONa是强碱弱酸盐,水解,促进水的电离,PH=11,C(H+)=10^-11mol/L,由水电离出的C(OH-)水=Kw/C(H+)=10^-14/10^-11=10^-3mol/L
因为加入0.05mol/L的CH3COONa,即加入了CH3COO-,它水解呈碱性,所以PH值变大.