INTRODUCTION
I. INTRODUCTION
The rate constant of the saponification reaction of ethyl acetate is a key parameter in the study of chemical kinetics, which reflects the rate characteristics of the chemical reaction. As a typical second-order reaction, the study of the rate constant of ethyl acetate saponification is of great significance. Experimental determination of the rate constant of this reaction not only helps to deeply understand the kinetic law of the second-order reaction, but also provides theoretical basis for related industrial production and chemical processes.

Second, experimental principle
The equation of the saponification reaction of ethyl acetate is: $CH_ {3} COOC_ {2} H_ {5} + NaOH\ longrightarrow CH_ {3} COONa + C_ {2} H_ {5} OH $. In dilute solution, this reaction can be regarded as a second-order reaction, and the reaction rate is proportional to the product of the concentration of ethyl acetate and sodium hydroxide. Suppose the initial concentration of ethyl acetate and sodium hydroxide at the beginning of the reaction is $a $, and the concentration of sodium acetate and ethanol produced by the reaction at $t $is $x $, then the reaction rate equation is: $v = k (a - x) (a - x) $, $k $is the reaction rate constant. As the reaction proceeds, the $OH ^ - $ions with strong conductivity in the solution are gradually replaced by the $CH_ {3} COO ^ - $ions with weak conductivity. The reaction process can be tracked by measuring the change of the conductivity of the solution.

III. EXPERIMENTAL MATERIALS AND METHODS
(I) EXPERIMENTAL MATERIALS
1. ** REACTIONS **: ethyl acetate (analytically pure), sodium hydroxide (analytically pure), deionized water.
2. ** Instruments **: conductivity meter, thermostatic water bath, pipette, volumetric flask, conical flask, etc.


(II) EXPERIMENTAL STEP
1. ** SOLUTION PREPARATION **
- Accurately weigh a certain amount of sodium hydroxide, dissolve it with deionized water, bandwidth evaluation in volumetric flask, and prepare a sodium hydroxide solution with a concentration of $0.0200mol/L $.
- Measure an appropriate amount of ethyl acetate, dilute it with deionized water and bandwidth evaluation to prepare an ethyl acetate solution at a concentration of $0.0200mol/L $.
2. ** Conductivity Measurement **
- Adjust the temperature of the thermostatic water bath to the specified temperature (e.g. 25 dollars ^ {\ circ} C $).
- Pipette $25mL $of sodium hydroxide solution and $25mL $of ethyl acetate solution respectively, inject them into a clean and dry conical bottle, quickly mix and start timing, and insert the electrode of the conductivity meter into the solution to record the conductivity value at regular intervals.
- Repeat the above steps to measure the change in conductivity during the reaction at different temperatures (e.g. 30 dollars ^ {\ circ} C $, 35 dollars ^ {\ circ} C $).

IV. Experimental data processing and analysis of results
(1) Data processing
is plotted with $\ frac {1} {k _ {t } - κ_{∞}}$ to $t $. According to the second-order reaction kinetic equation, the slope of the line is $m =\ frac {1} {ka} $, from which the reaction rate constant $k $can be calculated.

(2) Results analysis
1. ** Effect of temperature on reaction rate constants **: According to the reaction rate constants measured at different temperatures, using the Arrhenius formula $ln\ frac {k_ {2}} {k_ {1}} =\ frac {E_ {a}} {R} (\ frac {1} {T_ {1}} -\ frac {1} {T_ {2}}) $, the activation energy of the reaction can be calculated $E_ {a} $. With the increase of temperature, the reaction rate constant increases, indicating that the increase of temperature is beneficial to accelerate the saponification rate of ethyl acetate, which is consistent with Arrhenius theory.
2. ** Error Analysis **: The possible sources of errors in the experimental process include the accuracy of solution preparation, the stability of temperature control, and the error of conductivity measurement. For example, if there is a weighing or measuring error in solution preparation, the initial concentration will be inaccurate, which will affect the calculation result of the reaction rate constant; Temperature fluctuations may make the reaction system not always at the set temperature, which will affect the reaction rate.

Fifth, Conclusion
Through this experiment, the rate constant of ethyl acetate saponification reaction at different temperatures was successfully determined by conductivity method, and the effect of temperature on the reaction rate constant was analyzed. The experimental results provide data support for in-depth study of the kinetic characteristics of the reaction, and also deepen the understanding of the kinetic law of the second-order reaction. In future research and practical applications, the experimental conditions can be further optimized, the measurement accuracy can be improved, and a more reliable theoretical basis can be provided for the development of related fields.