某同学在两个相同的特制容器中分别加入20mL 0.4mol·L
-1Na
2CO
3溶液和40mL 0.2mol·L
-1NaHCO
3溶液,再分别用0.4mol·L
-1盐酸滴定,利用pH计和压强传感器检测,所得曲线如图。下列说法错误的是( )
![](http://tikupic.21cnjy.com/2024/05/04/bb/0f/bb0f5502d086fd9aeeb8460abae07a79.png)
已知:常温下,酚酞的变色范围是pH 8.2~10.0,甲基橙的变色范围是pH 3.1~4.4。
- A、曲线甲表示向Na2CO3溶液中滴加盐酸
- B、在b点无气体产生,此处发生反应的离子方程式为
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmtext%3EH%3C%2Fmtext%3E%3Cmtext%3EC%3C%2Fmtext%3E%3Cmsubsup%3E%3Cmrow%3E%3Cmtext%3EO%3C%2Fmtext%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E3%3C%2Fmn%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmo%3E%E2%88%92%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmsubsup%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmsup%3E%3Cmrow%3E%3Cmtext%3EH%3C%2Fmtext%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmo%3E%2B%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmsup%3E%3Cmtext%3E%3D%3C%2Fmtext%3E%3Cmsub%3E%3Cmrow%3E%3Cmtext%3EH%3C%2Fmtext%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E2%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3Cmtext%3EC%3C%2Fmtext%3E%3Cmsub%3E%3Cmrow%3E%3Cmtext%3EO%3C%2Fmtext%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E3%3C%2Fmn%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3C%2Fmath%3E)
- C、Na2CO3溶液或NaHCO3溶液中均有
![](https://math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmi%3Ec%3C%2Fmi%3E%3Cmrow%3E%3Cmo%3E%28%3C%2Fmo%3E%3Cmrow%3E%3Cmtext%3EN%3C%2Fmtext%3E%3Cmsup%3E%3Cmrow%3E%3Cmtext%3Ea%3C%2Fmtext%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmo%3E%2B%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmsup%3E%3C%2Fmrow%3E%3Cmo%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3Cmo%3E%26lt%3B%3C%2Fmo%3E%3Cmn%3E2%3C%2Fmn%3E%3Cmi%3Ec%3C%2Fmi%3E%3Cmrow%3E%3Cmo%3E%28%3C%2Fmo%3E%3Cmrow%3E%3Cmtext%3EC%3C%2Fmtext%3E%3Cmsubsup%3E%3Cmrow%3E%3Cmtext%3EO%3C%2Fmtext%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E3%3C%2Fmn%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E2%3C%2Fmn%3E%3Cmo%3E%E2%88%92%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmsubsup%3E%3C%2Fmrow%3E%3Cmo%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3Cmo%3E%2B%3C%2Fmo%3E%3Cmi%3Ec%3C%2Fmi%3E%3Cmrow%3E%3Cmo%3E%28%3C%2Fmo%3E%3Cmrow%3E%3Cmtext%3EH%3C%2Fmtext%3E%3Cmtext%3EC%3C%2Fmtext%3E%3Cmsubsup%3E%3Cmrow%3E%3Cmtext%3EO%3C%2Fmtext%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmn%3E3%3C%2Fmn%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmo%3E%E2%88%92%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmsubsup%3E%3C%2Fmrow%3E%3Cmo%3E%29%3C%2Fmo%3E%3C%2Fmrow%3E%3C%2Fmath%3E)
- D、滴定分析时,a点可用酚酞、c点可用甲基橙作指示剂指示滴定终点