what would be the concentration of chromate ion in a saturated solution of CaCrO4 (Ksp= 7.1x10^-4)
To determine the concentration of chromate ion in a saturated solution of CaCrO4, we need to use the solubility product constant, Ksp.
The balanced equation for the dissociation of CaCrO4 in water is:
CaCrO4 (s) ⇌ Ca2+ (aq) + CrO4^2- (aq)
The Ksp expression for the dissociation of CaCrO4 is:
Ksp = [Ca2+][CrO4^2-]
Since CaCrO4 is a 1:1 electrolyte, the concentration of Ca2+ and CrO4^2- ions will be the same when the compound is completely dissociated.
Therefore, let's assume that the concentration of Ca2+ and CrO4^2- ions in the saturated solution is x.
Thus, the Ksp expression becomes:
Ksp = x * x
Now, substitute the Ksp value (7.1 × 10^-4) into the equation:
7.1 × 10^-4 = x^2
Taking the square root of both sides:
x = √(7.1 × 10^-4)
Calculating this value gives:
x = 0.0267 M (rounded to four decimal places)
Therefore, the concentration of chromate ion (CrO4^2-) in a saturated solution of CaCrO4 is approximately 0.0267 M.
To determine the concentration of chromate ion (CrO4^-2) in a saturated solution of CaCrO4, you need to use the solubility product constant (Ksp) and the stoichiometry of the balanced equation.
The balanced equation for the dissociation of CaCrO4 is:
CaCrO4(s) ↔ Ca^2+(aq) + CrO4^2-(aq)
The Ksp expression for this equation is:
Ksp = [Ca^2+][CrO4^2-]
Since CaCrO4 is a sparingly soluble salt, it will dissociate very poorly into Ca^2+ and CrO4^2- ions. Thus, we can assume that the solubility of CaCrO4 is equal to the concentration of Ca^2+ and CrO4^2- ions in the saturated solution.
Let's assume that x represents the concentration of CrO4^2- ions in mol/L. Since the stoichiometry of the balanced equation is 1:1 for CaCrO4 and CrO4^2-, the concentration of Ca^2+ ions will also be x mol/L.
Substituting these values into the Ksp expression:
Ksp = [Ca^2+][CrO4^2-]
7.1x10^-4 = (x)(x)
7.1x10^-4 = x^2
To solve for x, take the square root of both sides:
√(7.1x10^-4) = x
Calculating this, we get:
x ≈ 0.0267 mol/L
Therefore, the concentration of chromate ion (CrO4^2-) in a saturated solution of CaCrO4 is approximately 0.0267 mol/L.