The enthalpy of formation for c6 h6 (i) is 49.0 kj/mol. consider the following reaction.

is the reaction endothermic or exothermic, and what is the enthalpy of reaction?

exothermic; mc014-3.jpghrxn = 49.0 kj
exothermic; mc014-4.jpghrxn = –49.0 kj
endothermic; mc014-5.jpghrxn = 49.0 kj
endothermic; mc014-6.jpghrxn = –49.0 kj

endothermic;

Explanation:

The balanced chemical reaction is,

The expression for enthalpy change is,

where,

n = number of moles

(as heat of formation of substances in their standard state is zero

(as heat of formation of substances in their standard state is zero

Now put all the given values in this expression, we get

Therefore, the enthalpy change for this reaction is +49.0 KJ

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and for the reaction comes out to be negative.

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and for the reaction comes out to be positive.

As heat change is positive, the reaction is endothermic and

the answer is na (sodium)