Question

Please help this is due today

Study the graph below to answer the question.


Reaction A is an exothermic process and reaction B is an endothermic process because
A.
the enthalpy change of reaction A is lower than that of reaction B.
B.
ΔH is positive for reaction A and ΔH is negative for reaction B.
C.
the energy of activation of reaction A is lower than that of reaction B.
D.
ΔH is negative for reaction A and ΔH is positive for reaction B.

Answer 1

Answer is: D. ΔH is negative for reaction A and ΔH is positive for reaction B.

There are two types of thermochemical reactions:

1) endothermic reaction (chemical reaction that absorbs more energy than it releases).

For example, ΔH(reaction) = 150 kJ/mol; this is endothermic reaction.

2) exothermic reaction (chemical reaction that releases more energy than it absorbs).

For example, ΔH(reaction) = -225 kJ/mol; this is exothermic reaction.

the change in enthalpy = the total bonding energy for the products of a reaction - the bonding energy of the reactants.