In which reaction will the point of equilibrium shift to the left when the pressure...
In which reaction will the point of equilibrium shift to the left when the pressure on the system is increased?
- A)C(s) + O\(_2\)(g) \(\iff\) CO\(_2\)(g)
- B)CaCO\(_3\)(s) \(\iff\) CaO(s) + CO\(_2\)(g)
- C)2Mg(s) + O\(_2\)(g) \(\iff\) 2MgO(s)
- D)2H\(_2\)(g) + O\(_2\)(g) \(\iff\) 2H\(_2\)O(g)
Correct Answer: B)CaCO\(_3\)(s) \(\iff\) CaO(s) + CO\(_2\)(g)
Explanation
When the pressure on a system is increased, the equilibrium shifts in the direction that has fewer moles of gas. This is because the side with fewer moles of gas will occupy a smaller volume, thereby reducing the pressure.
In this case, we need to identify the reaction that will have the equilibrium shift to the left when the pressure is increased:
Option A: C(s) + O\(_2\)(g) \(\iff\) CO\(_2\)(g)
In this reaction, there is 1 mole of gas on both sides, so increasing the pressure will not cause a shift in equilibrium.
Option B: CaCO\(_3\)(s) \(\iff\) CaO(s) + CO\(_2\)(g)(Correct)
In this reaction, there are no moles of gas on the left side and 1 mole of gas on the right side. Increasing the pressure will cause the equilibrium to shift to the left, which has fewer moles of gas.
Option C: 2Mg(s) + O\(_2\)(g) \(\iff\) 2MgO(s)
In this reaction, there is 1 mole of gas on the left side and no moles of gas on the right side. Increasing the pressure will cause the equilibrium to shift to the right, which has fewer moles of gas.
Option D: 2H\(_2\)(g) + O\(_2\)(g) \(\iff\) 2H\(_2\)O(g)
In this reaction, there are 3 moles of gas on the left side and 2 moles of gas on the right side. Increasing the pressure will cause the equilibrium to shift to the right, which has fewer moles of gas.
Therefore, the correct answer is Option B: CaCO\(_3\)(s) \(\iff\) CaO(s) + CO\(_2\)(g), as the equilibrium will shift to the left when the pressure is increased.