Answer:
The answer is "Option b".
Explanation:
Given equation and value:


calculating equation value:


Answer:
There are 8 valence electrons
Explanation:
<u>Answer:</u> The rate constant for the given reaction is 
<u>Explanation:</u>
For the given chemical equation:

We are given that the above equation is undergoing first order kinetics.
The equation used to calculate rate constant from given half life for first order kinetics:

The rate constant is independent of the initial concentration for first order kinetics.
We are given:
= half life of the reaction = 
Putting values in above equation, we get:

Hence, the rate constant for the given reaction is 
The second one.
Remember, temperature is the AVERAGE kinetic energy. So, looking for highest average kinetic energy means looking for highest temperature, which is 55.
Note: the amount of the substance does not determine the average kinetic energy.