For various types of acid-base titration, the position of the stoichiometric point is at the midpoint of the jump range.

Which one is the right analytical procedures? A: Sampling-Measurement-Calculations of results- Evaluation of data B: Sampling- Pretreatment-Measurement- Calculations and Evaluation of Data C: Sampling- Pretreatment-Titration- Calculations and Evaluation of data D: Sampling- Pretreatment-Measurement- Calculations of results

2. Which of the following methods is not commonly used to separate interfering components? ( ) A: Precipitation separation method B: Titration analysis C: Ion exchange method D: Chromatographic separation

滴定反应(Titration reaction)在接近终点(Endponit)时可加入半滴或四分之一滴滴定剂，用锥形瓶(Eelenmeyer flask)内壁将其沾落，再用洗瓶以少量纯水冲下。

In<br/>the acid-base titration of aspirin, neutral ethanol is required to be<br/>used as the solvent. What is the meaning of calling "neutral"?() A: neutral<br/>to the indicator used B: pH=7 C: ethanol<br/>to remove acidic impurities D: It<br/>is neutral to methyl orange E: relative<br/>to the tested substance

Point out the erroneous conclusions in the following statements ( ) A: The acid effect of complexing agent reduces the stability of complex B: The hydrolytic effect of metal ions reduces the stability of the complex C: The auxiliary complexation effect reduces the stability of the complex D: All kinds of side reactions are not conducive to the occurrence of the main reaction of complexometric titration