Determine Qsp if 8.7 ml of 2.1 M AgNO3 is added to 1.7 ml of 1.5 M CaCl2 .The Ksp of AgCl is 1.77 x 10^-10.
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7.7
To determine the solubility product constant (Ksp) of AgCl (silver chloride) when AgNO3 (silver nitrate) is added to CaCl2 (calcium chloride), we first need to understand the reaction that takes place.
The balanced chemical equation for the reaction between AgNO3 and CaCl2 is:
AgNO3(aq) + CaCl2(aq) -> AgCl(s) + Ca(NO3)2(aq)
From the balanced equation, we can see that 1 mole of AgNO3 reacts with 1 mole of CaCl2 to form 1 mole of AgCl and 1 mole of Ca(NO3)2.
Step 1: Calculate the moles of AgNO3 and CaCl2
Given:
Volume of AgNO3 (V1) = 8.7 ml = 0.0087 L
Molarity of AgNO3 (M1) = 2.1 M
Number of moles of AgNO3 (n1) = M1 * V1
n1 = 2.1 M * 0.0087 L = 0.01827 moles
Volume of CaCl2 (V2) = 1.7 ml = 0.0017 L
Molarity of CaCl2 (M2) = 1.5 M
Number of moles of CaCl2 (n2) = M2 * V2
n2 = 1.5 M * 0.0017 L = 0.00255 moles
Step 2: Determine the limiting reactant
To find the limiting reactant, compare the number of moles of AgNO3 and CaCl2.
The stoichiometry of the balanced equation shows that the ratio of AgNO3 to AgCl is 1:1, and the ratio of CaCl2 to AgCl is also 1:1.
Since the number of moles of AgNO3 (0.01827 moles) is greater than the number of moles of CaCl2 (0.00255 moles), CaCl2 is the limiting reactant.
Step 3: Calculate the moles of AgCl formed
Since the limiting reactant is CaCl2, the number of moles of AgCl formed is also equal to the number of moles of CaCl2.
Number of moles of AgCl formed = n2 = 0.00255 moles
Step 4: Calculate the concentration of Ag+ and Cl- ions in the solution
Since AgNO3 dissociates into Ag+ and NO3- ions, and CaCl2 dissociates into Ca2+ and 2Cl- ions, we need to consider the concentration of these ions.
The concentration of Ag+ ions is equal to the concentration of AgNO3, which is 2.1 M.
The concentration of Cl- ions is twice the concentration of CaCl2, which is 1.5 M. Therefore, the concentration of Cl- ions is 1.5 M * 2 = 3 M.
Step 5: Calculate the solubility product constant (Ksp) of AgCl
The solubility product constant (Ksp) expression for AgCl is:
Ksp = [Ag+] * [Cl-]
Substituting the concentrations we calculated:
Ksp = (2.1 M) * (3 M) = 6.3
Therefore, the solubility product constant (Ksp) of AgCl is 6.3.