How to Calculate the Enthalpy of Reaction of a Molecule – Part 1

The enthalpy of neutralization (ΔnHѲ) is the change in enthalpy that occurs when one equivalent of an acid and a base undergo a neutralization reaction to form water and a salt, and is a special case of the enthalpy of reaction.


The limiting reagent (aka limiting reactant/agent) in a chemical reaction is a reactant totally consumed when the chemical reaction is completed.

Checking the limiting reactant: To take the number of moles of each reactant and divide it by its stoichiometric coefficient in the balanced equation. The quotient with a lower value indicates the limiting reactant.

Question:

In the neutralization of a strong acid and a strong base, the enthalpy of formation of 1 mol of water is ─57.1 kJ. If 0.20 mol of a strong monoprotic acid reacts with 0.10 mol of a strong monohydroxy base, then what would be the enthalpy of neutralization?

Solution:



Click to enlarge the image

HA = Monoprotic acid, BOH = Monohydroxy base, BA = Salt of HA & BOH

Enthalpy enumerated easily ❓ Let Chemaficionado know at mychemistryhomework@gmail.com❗

References:

(1)    Limiting reagent. Wikipedia. https://en.wikipedia.org/wiki/Limiting_reagent.

‌(2)    Wikipedia Contributors. Enthalpy of neutralization. Wikipedia. https://en.wikipedia.org/wiki/Enthalpy_of_neutralization.

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