Answer:

Explanation:
Hello there!
In this case, according to the given chemical equation, it turns out possible for us to realize there is a 4:3 mole ratio of chromium(III) nitrate to lead(IV) nitrate, and therefore, we can calculate the moles of the former by applying the shown below stoichiometry setup:

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Answer:
84%
Explanation:
2100 j out / 2500 j in = .84 = 84%
By using this formula of vapor pressure:
Pv(solu)= n Pv(water)
when we have Pv(solu)=231.16 torr & Pv(water)= 233.7 torr
from this formula, we can get n (mole fraction of water) by substitution:
231.16 = n * 233.7
∴ n(mole fraction of water) = 0.99
so mole fraction of solution = 1 - 0.99 = 0.01
when no.of moles of water = mass weight / molar weight
= 365g / 18g/mol = 20 moles
Total moles in solution = moles of water / mole fraction of water
= 20 / 0.99 =20.2
no. of moles of the solution= total moles in solution- moles of water
= 20.2 - 20 = 0.2 moles
when we assumed the mass weight of the solution = 16 g (missing in your question should be given)
∴ molar mass = mass weight of solute / no. of moles of solute
= 16 g / 0.2 mol = 80 g/mol
Answer:
Should be A, but also I think there should be an arrow between O2 and 2H2O