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How does the rate of a chemical reaction change with an increase or decrease in temperature? Provide experimental evidence to support your answer.

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The rate of a chemical reaction is directly influenced by temperature. As the temperature increases, the rate of the reaction generally increases, and as the temperature decreases, the rate of the reaction decreases. This relationship can be explained by the Collision Theory and the Arrhenius Equation.According to the Collision Theory, a chemical reaction occurs when reactant molecules collide with sufficient energy and proper orientation. An increase in temperature leads to an increase in the kinetic energy of the molecules, causing them to move faster and collide more frequently. As a result, the number of effective collisions with the required activation energy also increases, leading to a faster reaction rate.The Arrhenius Equation mathematically describes the relationship between the rate constant  k  of a reaction and temperature  T :k = Ae^-Ea/RT where:- k is the rate constant- A is the pre-exponential factor  frequency of collisions with proper orientation - Ea is the activation energy  minimum energy required for the reaction to occur - R is the gas constant  8.314 J/mol K - T is the temperature in Kelvin- e is the base of the natural logarithm  approximately 2.718 As the temperature  T  increases, the exponential term e^-Ea/RT  becomes larger, leading to an increase in the rate constant  k  and thus a faster reaction rate. Conversely, as the temperature decreases, the exponential term becomes smaller, resulting in a slower reaction rate.Experimental evidence supporting this relationship can be found in numerous studies. One classic example is the reaction between hydrogen peroxide  H2O2  and potassium iodide  KI . In this reaction, hydrogen peroxide decomposes into water and oxygen gas, with potassium iodide acting as a catalyst:2H2O2  aq   2H2O  l  + O2  g By measuring the time it takes for a fixed amount of oxygen gas to be produced at different temperatures, the rate of the reaction can be determined. Results from such experiments consistently show that the reaction rate increases with increasing temperature.In conclusion, the rate of a chemical reaction generally increases with an increase in temperature and decreases with a decrease in temperature. This relationship is supported by the Collision Theory, the Arrhenius Equation, and experimental evidence from various chemical reactions, such as the decomposition of hydrogen peroxide catalyzed by potassium iodide.

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