The reaction
is the basis of a very ancient chemical industry. Seashells or chalk (limestone) are roasted in kilns to produce CaO (quicklime). When moistened and used in a mortar, this forms Ca(OH)₂ (slaked lime). Atmospheric CO₂ slowly converts this back to CaCO₃. A strong bond thus results between the stones used in the wall.
a. Is the above reaction exothermic or endothermic? Explain.
b. Lime kilns, since ancient times, have been designed with efficient chimneys to draw exhaust gases away. In terms of Le Chatelier's Principle, give two reasons why this enhances the conversion of limestone to quicklime.
c. When a sample of CaCO₃(s) is placed in a sealed, evacuated container, the equilibrium CO₂ pressure at a given temperature is always the same, and is not influenced by the amount of CaCO₃, provided that there is still some present at equilibrium. Explain why.
d. How would the result in Part c be affected by adding an equal number of moles of CaO to the flask? Explain.

Question

The reaction

is the basis of a very ancient chemical industry. Seashells or chalk (limestone) are roasted in kilns to produce CaO (quicklime). When moistened and used in a mortar, this forms Ca(OH)₂ (slaked lime). Atmospheric CO₂ slowly converts this back to CaCO₃. A strong bond thus results between the stones used in the wall.
a. Is the above reaction exothermic or endothermic? Explain.
b. Lime kilns, since ancient times, have been designed with efficient chimneys to draw exhaust gases away. In terms of Le Chatelier's Principle, give two reasons why this enhances the conversion of limestone to quicklime.
c. When a sample of CaCO₃(s) is placed in a sealed, evacuated container, the equilibrium CO₂ pressure at a given temperature is always the same, and is not influenced by the amount of CaCO₃, provided that there is still some present at equilibrium. Explain why.
d. How would the result in Part c be affected by adding an equal number of moles of CaO to the flask? Explain.

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The Answer of The reaction is the basis of a very ancient chemical industry. Seashells or chalk (limestone) are roasted in kilns to produce CaO (quicklime). When moistened and used in a mortar, this forms Ca(OH)₂ (slaked lime). Atmospheric CO₂ slowly converts this back to CaCO₃. A strong bond thus results between the stones used in the wall. a. Is the above reaction exothermic or endothermic? Explain. b. Lime kilns, since ancient times, have been designed with efficient chimneys to draw exhaust gases away. In terms of Le Chatelier's Principle, give two reasons why this enhances the conversion of limestone to quicklime. c. When a sample of CaCO₃(s) is placed in a sealed, evacuated container, the equilibrium CO₂ pressure at a given temperature is always the same, and is not influenced by the amount of CaCO₃, provided that there is still some present at equilibrium. Explain why. d. How would the result in Part c be affected by adding an equal number of moles of CaO to the flask? Explain.

The Reaction Is the Basis of a Very Ancient Chemical Industry