INTRODUCTION
INTRODUCTION
The rate constant of the saponification reaction of ethyl acetate is an important parameter in the study of chemical kinetics, which reflects the rate characteristics of the reaction. Taking the saponification reaction of ethyl acetate and sodium hydroxide as an example, in-depth exploration of the rate constant of the reaction is helpful to understand the kinetic law of such secondary reactions, which is of great significance to the fields of chemical industry, scientific research and other fields.

Reaction Principle
Ethyl acetate ($CH_3COOC_2H_5 $) undergoes a saponification reaction with sodium hydroxide ($NaOH $), and the chemical reaction equation is:
$CH_3COOC_2H_5 + NaOH\ longrightarrow CH_3COONa + C_2H_5OH $
This reaction is a second-order reaction, and its rate equation can be expressed as: $r = kc_ {A} c_ {B} $, where $r $is the reaction rate, $k $is the reaction rate constant, and $c_ {A} $, $c_ {B} $are the concentrations of reactants $A $ (ethyl acetate) and $B $ (sodium hydroxide) at a certain time.

Experimental Method
1. ** Experimental Instruments and Reagents **
A precise conductivity meter is used to measure the conductivity change of the reaction system. A constant temperature water bath is prepared to maintain the constant reaction temperature. It is equipped with a volumetric flask, a pipette, etc. to accurately measure the volume of the solution. The reagents include ethyl acetate solution and sodium hydroxide solution of known concentration.
2. ** Experimental Steps **
Under constant temperature conditions, a certain volume and concentration of sodium hydroxide solution is quickly poured into the reactor containing equal volume and equal concentration of ethyl acetate solution, and a stopwatch is started to record the time. During the reaction, the conductivity of the reaction system is measured at regular intervals using a conductivity meter. _t $. As the reaction progresses, the concentration of $NaOH $decreases continuously, and the generated $CH_3COONa $has a certain conductivity, and the conductivity of the system will gradually decrease. At the same time, the conductivity of the reaction system at the initial time is measured. At this time, it can be approximated that only $NaOH $contributes to the conductivity) and the conductivity of the system after the reaction is complete. $CH_3COONa $.

Data Processing and Results Analysis
1. ** Data Processing **
According to the second-order reaction kinetic equation and the relationship between conductivity and concentration, the following formula can be deduced:
$\ frac {k _0-k _t} {k _t - κ_∞} = kc _ 0 t $
where $c_0 $is the initial concentration of the reactant. Linear fitting is performed with $\ frac {k _0-k _t} {k _t - κ_∞}$ as the ordinate and $t $as the abscissa.
2. ** RESULTS ANALYSIS **
The slope of the straight line $m $is obtained by linear fitting. From the above formula, $m = kc_0 $, and the reaction rate constant $k =\ frac {m} {c_0} $can be calculated. Analyzing the rate constants obtained at different temperatures, we can further explore the effect of temperature on the reaction rate constant according to the Arrhenius formula $k = A e ^ {-\ frac {E_a} {RT}} $, and calculate the activation energy of the reaction $E_a $.

Conclusion
Through the experimental determination and analysis of the rate constants of the saponification reaction of ethyl acetate, we have determined the rate constants of the reaction under different conditions. As the temperature increases, the reaction rate constant increases, indicating that temperature has a significant effect on the reaction rate. This study provides an important experimental basis and theoretical support for in-depth understanding of secondary reaction kinetics and related chemical processes.