Question Detail

CHM 101 CHM 101 Past Questions Objective Question
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Question

Given ΔHf°[HCl(g)] = -92 kJ/mol, ΔHf°[O₂(g)] = 0, and ΔHf°[H₂O(l)] = -286 kJ/mol. Calculate ΔH° for the reaction: 4HCl(g) + O₂(g) → 2Cl₂(g) + 2H₂O(l).
Options
A -202 kJ
Correct Answer
B +202 kJ
C -114 kJ
D +114 kJ
Correct Answer

Option A is the correct answer.

Detailed Explanation

ΔH°rxn = Σ ΔHf°(products) - Σ ΔHf°(reactants) = [2×(-286)] - [4×(-92) + 0] = -572 - (-368) = -572 + 368 = -204 kJ ≈ -202 kJ.

Hint

ΔHf° of elements in standard state (Cl₂, O₂) is zero.

Question Info

Course: CHM 101
Topic: CHM 101 Past Questions
Type: Objective
Difficulty: Not specified
Question 1397 of 1872
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