For a one step reaction, the activation energy for the forward reaction is 40.0 kJ mol-1, and the enthalpy of reaction is -20.0 kJ mol-1. Calculate the activation energy for the reverse reaction.
Is my answer correct?
(40 kJ mol-1)-(-20 kJ mol-1) = 20kJ mol-1
I don't think so.
40 -(-20) = 60 and for an exothermic reaction you add Ea forward to |dH| so that is 40+20= 60 kJ/mol.
Your answer is incorrect. To calculate the activation energy for the reverse reaction, you need to use the fact that the activation energy for the forward reaction is equal to the difference between the enthalpy of reaction and the activation energy for the reverse reaction.
So, to find the activation energy for the reverse reaction, you need to subtract the enthalpy of reaction (-20 kJ mol-1) from the activation energy for the forward reaction (40 kJ mol-1).
40 kJ mol-1 - (-20 kJ mol-1) = 60 kJ mol-1
Therefore, the activation energy for the reverse reaction is 60 kJ mol-1.
No, your answer is incorrect. The activation energy for the reverse reaction is not equal to the difference between the activation energy and the enthalpy of the forward reaction.
To calculate the activation energy for the reverse reaction, you need to use the relationship between the activation energy for the forward reaction (Ea_f) and the activation energy for the reverse reaction (Ea_r) in the Arrhenius equation:
k_f = A * e^(-Ea_f / (RT))
k_r = A * e^(-Ea_r / (RT))
Where k_f is the rate constant for the forward reaction, k_r is the rate constant for the reverse reaction, A is the pre-exponential factor, R is the gas constant (8.314 J/(mol·K)), and T is the temperature in Kelvin.
The activation energy for the reverse reaction (Ea_r) can be calculated using the enthalpy of reaction (ΔH) as:
Ea_r = Ea_f - ΔH
Therefore, the activation energy for the reverse reaction is:
Ea_r = 40.0 kJ mol-1 - (-20.0 kJ mol-1) = 60.0 kJ mol-1
So, the correct answer is 60.0 kJ mol-1.
To calculate the activation energy for the reverse reaction in a one-step reaction, you can use the equation:
ΔH (reverse) = - ΔH (forward)
where ΔH represents the enthalpy of reaction.
Given that the enthalpy of reaction is -20.0 kJ mol-1 for the forward reaction, the enthalpy of reaction for the reverse reaction would also be -20.0 kJ mol-1.
However, please note that the activation energy for the reverse reaction cannot be directly obtained from the given information. The activation energy for the reverse reaction may or may not be the same as the activation energy for the forward reaction. It would require additional information or data to determine the activation energy for the reverse reaction.