H2o means water and co3 is co-signs
The two things are hypothesis and empirical evidence
I believe the correct answer from the choices listed above is option A. The topic that the teacher is talking about would be distillation of a mixture. Gasoline is processed by distillation. Hope this answers the question. Have a nice day.
They are different because they formed at different distances from the sun.
The combustion of naphthalene is given as:
C10H8 (s) + 12 O2 (g) --> 10CO2 (g) + 4 H2O (l)
Enthalpy of combustion ΔH = -5157 kJ/mol
Now, the enthalpy change of a reaction is given
ΔH = ∑nΔHf (products) - ∑nΔHf (reactants)
where n = number of moles
ΔHf = enthalpy of formation
Therefore,
ΔH = [10*ΔHf(CO2) + 4*ΔHf(H2O)] - [1*ΔHf(C10H8) + 12*O2]
-5157 = [10*(-393.5) + 4*(285.83)] - [ΔHf(C10H8) + 12*(0)]
ΔHf(C10H8) = 78.68 kJ/mol
