Question

$CaCO _{3}(s)+$ heat $\Longleftrightarrow CaO (s)+ CO _{2}(g)$ Le Chatelier's principle states that when a system at equilibrium is disfurbed, the systern will shift in the direction that will reduce the stress. Use the reaction above, and decide how the system will shift to oppose the stresses below. \begin{tabular}{|l|l|l|l} \hline STRESS & SHIFT & WHY? \\ \hline increase concentration of & eway from substance \\ a substance \end{tabular} Celumn A Golumn 10 1____ The temperature of the system is decreased when heat is removed from the systen. 2.____ The temperature of the systam is incressed when more heat is added 3.____ More $CaCO _{3}$ (caticium carbonate) is added to the syitern. 4____ More CaO (caicum onide) is added to the system. 5____ $CaCO _{2}$ (calcium catbonate) is removed fiom the system 6____ Cerbon dimaide $\left( CO _{2}\right)$ i2 rerrioved from the systern. Twe lerg for thas

Answer 1

To analyze how the system will shift in response to the specified stresses, we apply Le Chatelier's principle. The reaction is:

\[ CaCO_3(s) + \text{heat} \rightleftharpoons CaO(s) + CO_2(g) \]

Let’s fill in the table for each stress:

\[
\begin{array}{|l|l|l|l}
\hline
\text{STRESS} & \text{SHIFT} & \text{WHY?} \\
\hline
1. \text{The temperature of the system is decreased when heat is removed from the system.} & \text{Right} & \text{The forward reaction produces heat, so removing heat shifts equilibrium to produce more heat.} \\
\hline
2. \text{The temperature of the system is increased when more heat is added.} & \text{Left} & \text{Adding heat shifts equilibrium in the direction that consumes heat (the reverse reaction).} \\
\hline
3. \text{More } CaCO_3 \text{ (calcium carbonate) is added to the system.} & \text{Right} & \text{Increasing the concentration of reactants shifts the equilibrium to produce more products.} \\
\hline
4. \text{More } CaO \text{ (calcium oxide) is added to the system.} & \text{Left} & \text{Increasing the concentration of products shifts the equilibrium to produce more reactants.} \\
\hline
5. \text{ } CaCO_3 \text{ (calcium carbonate) is removed from the system.} & \text{Left} & \text{Removing reactants shifts the equilibrium to produce more reactants.} \\
\hline
6. \text{Carbon dioxide } (CO_2) \text{ is removed from the system.} & \text{Left} & \text{Removing a product shifts the equilibrium to produce more products.} \\
\hline
\end{array}
\]

In summary:
- Adding reactants or heat shifts right (forward direction).
- Removing reactants or products or decreasing temperature shifts left (reverse direction).