Calculate The $\Delta$ H_f $\degree$ Rxn for the Decomposition of Calcium Carbonate to Calcium Oxide

question 37

Multiple Choice

Calculate the $\Delta$ H_f $\degree$ rxn for the decomposition of calcium carbonate to calcium oxide and carbon dioxide.
$\Delta$ H_f $\degree$ [CaCO₃(s) ] = -1206.9 kJ/mol; $\Delta$ Hf _{$\degree$ [}CaO(s) ] = -635.1 kJ/mol; $\Delta$ H_fB0 [CO₂(g) ] = -393.5 kJ/mol. CaCO₃(s) $\rightarrow$ CaO(s) + CO₂(g)

• A) -2235.5 kJ
• B) -1448.5 kJ
• C) -178.3 kJ
• D) 178.3 kJ
• E) 2235.5 kJ

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Definitions:

Predetermined Overhead Rate

A rate calculated before the accounting period begins, used to estimate the cost of manufacturing overhead for a specific activity base.

Machine-Hours

An indicator of the time spent in production, calculating the duration in hours that machinery is active during the manufacturing cycle.

Direct Labor-Hours

The accumulated hours spent by workers directly involved in manufacturing activities.

Forming

A manufacturing process used to shape metal or other materials using a combination of pressure and tooling.