Answer:
Option A. Addition
Explanation:
Unsaturated compounds under goes addition reaction to produce saturated compounds..
In the equation given above i.e
H2C=CH2 + F–F —> FCH2CH2F
we can see that the double in H2C=CH2 disappear by the reaction of F–F to produce FCH2CH2F which has no double. This simply indicates that the F–F was added to H2C=CH2. Hence, the reaction is called addition reaction.
Answer:

Explanation:
Hello!
In this case, since we are considering an gas, which can be considered as idea, we can write the ideal gas equation in order to write it in terms of density rather than moles and volume:

Whereas MM is the molar mass of the gas. Now, since we can identify the initial and final states, we can cancel out R and MM since they remain the same:

It means we can compute the final density as shown below:

Now, we plug in to obtain:

Regards!
Hello there,
Your correct answer would be "<span>the energy of a photon".
Hope this helps.
~Hottwizzlers
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