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Wittaler [7]
3 years ago
13

Determine the enthalpy change of the following reaction: 2KClO3 -> 2KCl + 3O2

Chemistry
1 answer:
DerKrebs [107]3 years ago
4 0

Answer:

- 90.6 kJ/mol.

Explanation:

  • The enthalpy change of the reaction (ΔHrxn) is the difference between the sum of heat of formation of products and reactants.

<em>ΔHrxn = ∑ΔHf(products) - ∑ΔHf(reactants)</em>

<em></em>

  • For the reaction: <em>2KClO₃ → 2KCl + 3O₂,</em>

∴ ΔHrxn = ∑ΔHf(products) - ∑ΔHf(reactants)

∴ ΔHrxn = [(2*ΔHf(KCl)) + (3*ΔHf(O₂))] - [(2*ΔHf(KClO₃))] = [(2*(- 436.7 kJ/mol)) + (3*(0)] - [(2*(- 391.4 kJ/mol)] = [- 873.4 kJ/mol] - [- 782.8 kJ/mol] = - 90.6 kJ/mol.

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