Question 8.8: USING STANDARD HEATS OF FORMATION TO CALCULATE ΔH° Calculate...

USING STANDARD HEATS OF FORMATION TO CALCULATE ΔH°

Calculate ΔH° in kilojoules for the synthesis of lime (CaO) from limestone ( $CaCO_{3}$ ), the key step in the manufacture of cement.

$CaCO_{3}(s) → CaO(s) + CO_{2}(g)$ $ΔH°_{f} [CaCO_{3}(s)]$ = -1207.6 kJ/mol

$ΔH°_{f}[CaO(s)]$ = -634.9 kJ/mol

$ΔH°_{f} [CO_{2}(g)]$ = -393.5 kJ/mol

STRATEGY
Subtract the heat of formation of the reactant from the sum of the heats of formation of the products.

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