<u>Answer:</u> The activation energy of the reverse reaction is 47 kJ/mol
<u>Explanation:</u>
The chemical equation for the decomposition of dinitrogen pentaoxide follows:

We are given:
Activation energy of the above reaction (forward reaction) = 102 kJ/mol
Enthalpy of the reaction = +55 kJ/mol
As, the enthalpy of the reaction is positive, the reaction is said to be endothermic in nature.
To calculate the activation energy for the reverse reaction, we use the equation:

where,
= Activation energy of the forward reaction = 102 kJ/mol
= Activation energy of the backward reaction = ?
= Enthalpy of the reaction = +55 kJ/mol
Putting values in above equation, we get:

Hence, the activation energy of the reverse reaction is 47 kJ/mol
I’ve only had one and it didn’t flow so ion think so
Answer:
I think the first option is the answer
Tc-99m<span> is a </span>metastable isomer<span> of </span>Tc-99. It finds widespread applications in <span>medical diagnostic procedures.
</span>
Tc-99 is also a radioactive element. It's half-life is 2,11,000 years. Upon radioactive decay, it emits beta particles and gets converted into stable compound Ruthenium-99
This process of radioactive decay is shown below.
99 43Tc → 99 44Ru + 0 -1e
(stable) (β particle)