Question

The heat of neutralization is highest in the reaction between:
A. $HN{{O}_{3}}\text{ }and\text{ }N{{H}_{4}}OH$
B. $HCl$ $and$ $NaOH$
C. $N{{H}_{4}}OH\text{ }and\text{ }C{{H}_{3}}COOH$
D. $NaOH\text{ }and\text{ }C{{H}_{3}}COOH$

Answer 1

Heat of neutralization means the amount of heat is going to liberate when an acid is going to react with a base. We can call it enthalpy sometimes. Whenever an acid is going to react with base a neutral compound (salt) is going to form as the product.

Complete step by step answer:
- In the question it is given that the heat of neutralization is highest for which chemicals among the given options.
- We know that the heat of neutralization (amount of heat liberated) is high when a strong acid is going to react with a strong base.
- We have to find the strong acid and strong base among the given options.
- Coming to the given options. Option A, $HN{{O}_{3}}\text{ }and\text{ }N{{H}_{4}}OH$ . We know that nitric acid is a strong acid and ammonium hydroxide is a weak base.
- Coming to the option B, HCl and NaOH. We know that hydrochloric acid is a strong acid and sodium hydroxide is a strong base.
- Coming to the option C, $N{{H}_{4}}OH\text{ }and\text{ }C{{H}_{3}}COOH$ . We know that ammonium hydroxide is a weak base and acetic acid is a weak acid.
- Coming to the option D, $NaOH\text{ }and\text{ }C{{H}_{3}}COOH$. We know that sodium hydroxide is a strong base and acetic acid is a weak acid.
- Therefore hydrochloric acid is a strong acid and sodium hydroxide is a strong base resulting in the formation of high heat of neutralization.

So, the correct option is B.

Note: At the time of neutralization reaction of an acid with a base, some amount of energy is going to be used to ionize the acid and base in the respective solvent. In a neutralization reaction the products which are going to form are a salt and water.