<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
The primary difference between a hypothesis and a theory is that a hypothesis is falsifiable but a theory has been proven to be correct. An hypothesis is a proposed explanation put forward on the basis of limited evidence as a commencement point for further investigation, at the end of the investigation the theory may not be accepted if it failed to meet some criteria. A theory is a proven system of ideas used to explain a particular phenomenon.
Answer: Titanium has 22 protons
Explanation: If an atoms donates 4 electrons, it forms cation with charge +4. So original atom have 22 electrons and because atom is neutral, it has 22 protons. Number of neutrons does not matter, there are more neutrons than protons in heavier atoms.
C hope that helps have a good one
C because the more amounts of mass an object has will give it a bigger gravitational field