用强碱滴定某一元弱酸时,弱酸被强碱部分中和后可得到“弱酸和弱酸盐”组成的缓冲溶液,缓冲溶液的pH=pK
m-lg
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmrow%3E%3Cmfrac%3E%3Cmrow%3E%3Cmtext%3Ec%3C%2Fmtext%3E%3Cmrow%3E%3Cmo%3E%28%3C%2Fmo%3E%3Cmtext%3E%E9%85%B8%3C%2Fmtext%3E%3Cmo%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmtext%3Ec%3C%2Fmtext%3E%3Cmrow%3E%3Cmo%3E%28%3C%2Fmo%3E%3Cmtext%3E%E7%9B%90%3C%2Fmtext%3E%3Cmo%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmrow%3E%3C%2Fmfrac%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
(计算时忽略酸的电离和盐的水解)。常温下,用0.1mol·L
-1的NaOH溶液滴定16.00mL某未知浓度的HX溶液,滴定过程中消耗NaOH溶液的体积与混合溶液pH之间的关系如图(已知:pK
m=-lgK
m , 10
0.48≈3.0)。下列说法正确的是( )
- A、滴定前HX溶液的浓度约为0.3mol·L-1
- B、HX的电离常数Ka=10-3.79
- C、n点溶液中存在c(X-)+2c(OH-)=c(HX)+2c(H+)
- D、q点液中离子浓度的大小关系为c(Na+)>c(X-)