Discussion on acid-base neutralization titration in high school chemistry

The standard solution is an acidic solution, and the solution to be tested is an alkaline solution. The result of titration of the alkaline solution to be tested by the standard acidic solution shall prevail. In fact, here c (to be measured) =c (standard) * v (standard) /v (to be measured), c (standard), v (standard) and v (to be measured) are all known or measurable, and only the errors of these quantities will lead to titration errors. For example, C (standard) is too small, for example, it is not washed, the numerator on the right side of the equal sign is too small, the denominator remains unchanged, the fractional value is too small, and the mass concentration of the liquid to be measured is too small; For example, when measuring the standard solution (looking up or down), there is an error in the reading, and the molecules will become larger and smaller accordingly, and the final result is also wrong. Therefore, for large and small analysis, it is enough to focus on large and small chemical quantities.

Let's talk about the wetting operation first. Moisturizing is only used for burette and pipette, because burette and pipette will be cleaned with clean water after use. Because these two measuring instruments have high precision, they are generally used in experiments with high precision requirements, so the influence of clear water will lead to experimental errors, which is why it is often necessary to use the measured liquid before use to reduce the errors. Wetting and washing operations cannot be used in conical bottles, which is related to the use of conical bottles in titration experiments. The conical bottle is only used to hold the liquid to be measured, and the corresponding burette is used when measuring a certain volume of liquid to be measured. V (to be measured) is also determined by the reading of burette. According to the principle of acid-base neutralization, as long as the total substance of the tested liquid remains unchanged, the total substance of the standard liquid will not change. Therefore, the conical bottle can be washed with clean water (clean water does not change the total mass of the measured liquid) but it cannot be wetted with the measured liquid (changing the total mass of the measured liquid is equivalent to adding the measured liquid, and the actual measured liquid is more than the measured liquid, which makes the C of the measured liquid larger).

That's about it. The rest can be analyzed as long as the actual and measured values are well grasped.