hydrogen bromide breaks down into diatomic hydrogen and bromine in the reaction shown.
2HBr > H2 + Br2
the energy of the reactant is 732 kJ/mol, and the energy of the products is 630 kJ/mol.
what is the total energy of the reaction? is this reaction endothermic or exothermic?
a ) -102 kJ/mol, endothermic
b ) 102 kJ/mol, endothermic
c ) 102 kJ/mol, exothermic
d ) -102 kJ/mol, exothermic
To determine the total energy of the reaction and whether the reaction is endothermic or exothermic, you subtract the energy of the products from the energy of the reactants:
Energy of reaction = Energy of products - Energy of reactants
= 630 kJ/mol - 732 kJ/mol
= -102 kJ/mol
The negative sign indicates that the reaction releases energy. Therefore, the reaction is exothermic.
The correct answer is:
d) -102 kJ/mol, exothermic