True and False...
1. A thermodynamically favorable reaction also proceeds spontaneously.
I think that it is false?
2. Doubling the concentration of a reactant always causes the reaction rate to double.
3. a reaction that has a large activation energy in the forward direction direction will also have a large activation energy in the reverse.
I think this one will be false too....?
4. A reaction is favorable if the free energy change is negative...... true?
I think 1 is true.
2 is true in most cases but not in all; therefore, I would vote for false. (There are some reactions [zero order] where the concentration is not a factor. See (Broken Link Removed)
I think you are right for 3.
4 is true
1. True and False. A thermodynamically favorable reaction generally has a negative change in free energy (ΔG), indicating that the reaction is spontaneous under certain conditions. However, a thermodynamically favorable reaction may not always proceed spontaneously if it has a high activation energy barrier. So, the statement is partly true but can be false in some cases.
To determine whether a reaction proceeds spontaneously, you can calculate the change in free energy using the equation ΔG = ΔH - TΔS, where ΔH is the change in enthalpy, ΔS is the change in entropy, and T is the temperature in Kelvin. If ΔG is negative, the reaction is thermodynamically favorable and is likely to proceed spontaneously under normal conditions.
2. False. Doubling the concentration of a reactant does not always cause the reaction rate to double. The rate of a chemical reaction depends on factors such as temperature, concentration of reactants, presence of catalysts, and the reaction mechanism. The relationship between concentration and reaction rate is determined by the reaction's rate law, which can be different for different reactions. In some cases, doubling the concentration of a reactant may increase the reaction rate more than twofold, while in other cases, it may have little to no effect on the rate. Therefore, the statement is false.
3. True. A reaction that has a large activation energy in the forward direction will generally also have a large activation energy in the reverse direction. The activation energy represents the energy barrier that reactants must overcome to form products. If a reaction has a high activation energy in one direction, it means that more energy is required for the reactants to reach the transition state and proceed to the products. The same energy barrier needs to be overcome in the reverse direction for the products to transform back into reactants, leading to a large activation energy in the reverse direction as well. Therefore, the statement is true.
4. True. A reaction is considered favorable if the change in free energy (ΔG) is negative. A negative ΔG indicates that the reaction is thermodynamically spontaneous, meaning that the reaction is energetically favorable and can occur without an external input of energy. On the other hand, a positive ΔG indicates that the reaction is thermodynamically unfavorable, and an input of energy is required for the reaction to proceed. Therefore, if the free energy change (ΔG) is negative, the reaction is considered favorable.