If Qsp< Ksp , then precipitation will not occur. A. True B. False
The correct answer and explanation is:
The correct answer is A. True.
Explanation:
The terms Qsp (reaction quotient) and Ksp (solubility product constant) are used in the context of solutions, particularly in understanding whether a solid will precipitate from a saturated solution.
- Qsp (reaction quotient): This is a measure of the concentration of ions in a solution at any given point, whether the system is at equilibrium or not. It is calculated using the same formula as Ksp, but the ion concentrations used to compute Qsp are not necessarily those of a saturated solution.
- Ksp (solubility product constant): This is the equilibrium constant for the dissolution of a solid into ions in a saturated solution. It is specific to a given compound and temperature. The Ksp represents the maximum concentration of ions that can be present in the solution before the compound starts to precipitate out of solution.
The condition Qsp < Ksp means that the concentration of ions in the solution is lower than the equilibrium concentration. In this case, the solution is unsaturated, meaning it can still dissolve more of the solid without precipitating. Therefore, no precipitation will occur because the solution has not yet reached the point where the concentration of ions exceeds the solubility limit (Ksp).
In contrast:
- If Qsp > Ksp, the concentration of ions is higher than the solubility equilibrium, and this supersaturated condition leads to precipitation of the solid.
- If Qsp = Ksp, the solution is saturated and at equilibrium, meaning no more solid will dissolve, nor will any solid precipitate out.
In summary, when Qsp < Ksp, the solution is not saturated enough for precipitation to occur, and therefore precipitation will not take place.