Determine the Enthalpy Change for the Decomposition of Calcium Carbonate

question 2

Multiple Choice

Determine the enthalpy change for the decomposition of calcium carbonate CaCO₃(s) ? CaO(s) + CO₂(g)
Given the thermochemical equations below.
$$\begin{array} { l l } \mathrm { Ca } ( \mathrm { OH } ) _ { 2 } ( \mathrm {~s} ) \rightarrow \mathrm { CaO } ( \mathrm { s } ) + \mathrm { H } _ { 2 } \mathrm { O } ( \ell ) & \Delta _ { r } H ^ { \circ } = 65.2 \mathrm {~kJ} / \mathrm { mol } - \mathrm { rxn } \\\mathrm { Ca } ( \mathrm { OH } ) _ { 2 } ( \mathrm {~s} ) + \mathrm { CO } _ { 2 } ( \mathrm {~g} ) \rightarrow \mathrm { CaCO } _ { 3 } ( \mathrm {~s} ) + \mathrm { H } _ { 2 } \mathrm { O } ( \ell ) & \Lambda _ { r } H ^ { \circ } = - 113.8 \mathrm {~kJ} / \mathrm { mol } - \mathrm { rxn } \\\mathrm { C } ( \mathrm { s } ) + \mathrm { O } _ { 2 } ( \mathrm {~g} ) \rightarrow \mathrm { CO } _ { 2 } ( \mathrm {~g} ) & \Delta _ { r } H ^ { \circ } = - 393.5 \mathrm {~kJ} / \mathrm { mol } - \mathrm { rxn } \\2 \mathrm { Ca } ( s ) + \mathrm { O } _ { 2 } ( \mathrm {~g} ) \rightarrow 2 \mathrm { CaO } ( \mathrm { s } ) & \Delta _ { r } H ^ { \circ } = - 1270.2 \mathrm {~kJ} / \mathrm { mol } - \mathrm { rxn }\end{array}$$

• A) +48.6 kJ/mol-rxn
• B) +179.0 kJ/mol-rxn
• C) +345.5 kJ/mol-rxn
• D) +441.0 kJ/mol-rxn
• E) +1711.7 kJ/mol-rxn

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Definitions:

Light

Light is electromagnetic radiation within a portion of the electromagnetic spectrum that can be perceived by the human eye, responsible for the sense of sight.

Chemical Energy

Energy stored in the bonds of chemical compounds and released in a chemical reaction, often producing heat as a by-product.

Carbon Dioxide Fixation

The process of converting carbon dioxide into organic compounds, such as glucose, during photosynthesis.

Rubisco

An enzyme involved in the first major step of carbon fixation, a process by which atmospheric carbon dioxide is converted by plants to energy-rich molecules.