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Combustion can be defined as the reaction of a compound with oxygen. The enthalpy of combustion of octane is
for
.
<h3>What is the enthalpy of reaction?</h3>
The enthalpy of reaction is the amount of heat energy absorbed or lost by the molecules in the chemical reaction.
The enthalpy of combustion is the amount of heat energy released by the compound in the reaction with oxygen.
The reaction in which heat is liberated with the reaction of a compound with oxygen has an enthalpy of combustion, equivalent to the enthalpy of reaction.
The combustion of octane can be given as:

Thus, the reaction has combustion energy equivalent to the enthalpy of the reaction is
. Thus, option B is correct.
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While metallic bonds have the strong electrostatic force of attractions between the cation or atoms and the delocalized electrons in the geometrical arrangement of the two metals. ... Metallic bonds are malleable and ductile, while covalent bonds and ionic bonds non-malleable and non-ductile.
I'm not the best with science but I believe the answer is B. Na.
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