Answer:

Explanation:
Hello,
In this case, the enthalpy of combustion is understood as the energy released when one mole of fuel, in this case octene, is burned in the presence of oxygen and is computed with the enthalpies of formation of the fuel, carbon dioxide and water as shown below (oxygen is circumvented as it is a pure element):

Thus, since we already know the enthalpy of combustion of the fuel, for carbon and water we have -393.5 and -241.8 kJ/mol respectively, thereby, the enthalpy of combustion turns out:

Best regards.
B is the right answer "right"
Answer:
285.185 (.185 repeating) cm^3
Explanation:
To get the answer, you divide 140 by 27 to get 5.185 (.185 repeating). Then, you multiply 5.185 (.185 repeating) by 55 and get 285.185 (.185 repeating) cm^3. Please use ^ next time to indicate exponents.
The answer is A :) homogeneous!