Answer:

Explanation:
Hello,
In this case, since the acid is monoprotic, we can notice a 1:1 molar ratio between, therefore, for the titration at the equivalence point, we have:

Thus, solving for the moles of the acid, we obtain:

Then, by using the mass of the acid, we compute its molar mass:

Regards.
B) Exothermic
The reaction released heat energy to its surrounding, thus, it was exothermic.
"exo" is to expel or put outside
"thermic" means heat
I don't know how 5°C cooled to 85°C but the answer would be 12.878L
3rd level would able to hold a max of 18 elelctrons