True or false: High temperatures are favorable to a reaction both kinetically and thermodynamically. Explain.

Kinetics refers to the study of the rates of chemical reactions, while thermodynamics focuses on the energy changes associated with reactions. Kinetically favored reactions are those that occur at a faster rate, while thermodynamically favored reactions are those that have a favorable change in energy, such as Gibbs free energy (ΔG).

According to the Arrhenius equation, the rate constant k of a reaction is related to the temperature T by the formula: \[k = Ae^{\frac{-E_a}{RT}}\] where A is the pre-exponential factor, \(E_a\) is the activation energy, R is the gas constant, and T is the temperature in Kelvin. As the temperature increases, the exponential term becomes smaller due to the negative sign in the exponent. This results in a larger rate constant, k, which means the reaction occurs at a faster rate. So, kinetically, high temperatures are favorable for a reaction.

In thermodynamics, the Gibbs free energy change (ΔG) for a reaction is related to the enthalpy change (ΔH), the temperature in Kelvin (T), and the entropy change (ΔS) by the equation: \[ΔG = ΔH - TΔS\] For a reaction to be thermodynamically favorable (spontaneous), the Gibbs free energy change (ΔG) should be negative. Whether high temperatures are favorable for a reaction thermodynamically depends on the values of ΔH and ΔS. There are four possible cases depending on the signs of ΔH and ΔS: 1. ΔH < 0 and ΔS > 0: This means the reaction is exothermic and has an increase in entropy, so high temperatures are favorable for the reaction thermodynamically (ΔG is negative). 2. ΔH > 0 and ΔS < 0: In this case, the reaction is endothermic and has a decrease in entropy, so high temperatures are not favorable for the reaction thermodynamically (ΔG becomes less negative or positive). 3. ΔH < 0 and ΔS < 0: Here, the reaction is exothermic but has a decrease in entropy. The favorability of high temperature for the reaction depends on the magnitudes of ΔH and ΔS (high temperatures may or may not be favorable). 4. ΔH > 0 and ΔS > 0: In this case, the reaction is endothermic and has an increase in entropy. Again, the favorability of high temperature for the reaction depends on the magnitudes of ΔH and ΔS (high temperatures may or may not be favorable). In summary, while high temperatures are favorable for the kinetics of a reaction, they may or may not be favorable for the thermodynamics of the reaction depending on the enthalpy and entropy changes.

The statement is partially true. High temperatures are favorable to a reaction kinetically, but thermodynamically, it depends on the enthalpy and entropy changes of the specific reaction.