100 m l 0.5 N H 2 S O 4 (strong acid) is neutralized with 200 m l 0.2 MN H 4 O H in a constant pressure calorimeter, which results in a temperature rise of 1. 4 ∘ C . If the heat capacity of the

Question

100 m l 0.5 N H 2 ​ S O 4 ​ (strong acid) is neutralized with 200 m l 0.2 MN H 4 ​ O H in a constant pressure calorimeter, which results in a temperature rise of 1. 4 ∘ C . If the heat capacity of the calorimeter content is 1.5 k J / ∘ C , which statement is incorrect? H Cl + N a O H ⟶ N a Cl + H 2 ​ O + 57 k J C H 3 ​ COO H + N H 4 ​ O H ⟶ C H 3 ​ COON H 4 ​ + H 2 ​ O + 48.1 k J

TestHub · Accepted Answer

Heat Evolved: The heat released during neutralization is $q = C \times Δ T = 1.5 k J /℃ \times 1.4℃ = 2.1 k J$

Limiting Reagent: Equivalents of H₂SO₄ = $0.1 \times 0.5 = 0.05$ , and equivalents of NH₄OH = $0.2 \times 0.2 = 0.04$ (limiting reagent).

Enthalpy of Neutralization (A): $Δ H_{n e u t} = - \frac{2.1 k J}{0.04 e q} = - 52.5 k J / m o l$ , making statement (A) correct.

Dissociation of NH₄OH (B): $Δ H_{d i ss} (N H_{4} O H) = - 52.5 - (- 57) = 4.5 k J / m o l$ , making statement (B) correct.

Dissociation of CH₃COOH (C): $Δ H_{d i ss} (C H_{3} COO H) = - 48.1 - (- 57) - 4.5 = 4.4 k J / m o l$ , making statement (C) incorrect.

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