Skip to main content
Ch.17 - Additional Aspects of Aqueous Equilibria
Chapter 17, Problem 10b

Ca1OH22 has a Ksp of 6.5 * 10-6. (b) If 50 mL of the solution from part (a) is added to each of the beakers shown here, in which beakers, if any, will a precipitate form? In those cases where a precipitate forms, what is its identity? [Section 17.6]
Four beakers labeled (i) to (iv) with different solutions for precipitation analysis.

Verified step by step guidance
1
Determine the concentration of Ca1OH22 in the 50 mL solution from part (a).
Calculate the moles of Ca1OH22 in the 50 mL solution using the concentration and volume.
Identify the ions present in each beaker and their initial concentrations before mixing with the Ca1OH22 solution.
Calculate the final concentrations of the ions after mixing the 50 mL Ca1OH22 solution with the 75 mL solutions in each beaker.
Compare the ion product (Q) with the Ksp value of Ca1OH22 to determine if a precipitate will form in each beaker. If Q > Ksp, a precipitate will form, and identify the precipitate.

Verified Solution

Video duration:
17m
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Solubility Product Constant (Ksp)

The solubility product constant (Ksp) is an equilibrium constant that applies to the solubility of sparingly soluble ionic compounds. It quantifies the extent to which a compound can dissolve in water, expressed as the product of the molar concentrations of its constituent ions, each raised to the power of their coefficients in the balanced equation. For calcium hydroxide, Ca(OH)2, a Ksp of 6.5 x 10^-6 indicates that at equilibrium, the product of the concentrations of Ca²⁺ and OH⁻ ions will equal this value.
Recommended video:
Guided course
01:47
Solubility Product Constant

Precipitation Reaction

A precipitation reaction occurs when two soluble salts react in solution to form an insoluble compound, known as a precipitate. This process is driven by the formation of a product that has a lower solubility than the reactants. To determine if a precipitate will form, one must compare the ion product (Q) of the solution to the Ksp; if Q exceeds Ksp, a precipitate will form. In this case, the addition of Ca(OH)2 to the beakers will be analyzed for potential precipitate formation.
Recommended video:
Guided course
01:53
Selective Precipitation

Ion Concentration and Dilution

Ion concentration refers to the amount of a specific ion present in a solution, typically expressed in molarity (M). When solutions are mixed, the total volume increases, which can dilute the concentrations of the ions involved. The dilution factor can be calculated using the formula C1V1 = C2V2, where C is concentration and V is volume. Understanding how dilution affects ion concentrations is crucial for predicting whether the conditions will lead to precipitation in the beakers.
Recommended video:
Guided course
00:58
Dilution Equation
Related Practice
Textbook Question

Match the following descriptions of titration curves with the diagrams: (d) strong base added to polyprotic acid. [Section 17.3]

425
views
Open Question
(a) Will Co(OH)2 precipitate from solution if the pH of a 0.020 M solution of Co(NO3)2 is adjusted to 8.5? (b) Will AgIO3 precipitate when 20 mL of 0.010 M AgNO3 is mixed with 10 mL of 0.015 M NaIO3? The Ksp of AgIO3 is 3.1 * 10^-8.
Textbook Question

The following graphs represent the behavior of BaCO3 under different circumstances. In each case, the vertical axis indicates the solubility of the BaCO3 and the horizontal axis represents the concentration of some other reagent. (a) Which graph represents what happens to the solubility of BaCO3 as HNO3 is added? [Section 17.5]

698
views
Textbook Question

Three cations, Ni2+ , Cu2+ , and Ag+, are separated using two different precipitating agents. Based on Figure 17.23, what two precipitating agents could be used? Using these agents, indicate which of the cations is A, which is B, and which is C.[Section 17.7]

422
views
Textbook Question

Which of these statements about the common-ion effect is most correct? (a) The solubility of a salt MA is decreased in a solution that already contains either M+ or A-. (b) Common ions alter the equilibrium constant for the reaction of an ionic solid with water. (c) The common-ion effect does not apply to unusual ions like SO32 - . (d) The solubility of a salt MA is affected equally by the addition of either A- or a noncommon ion.

999
views
Textbook Question

Consider the equilibrium B1aq2 + H2O1l2 Δ HB+1aq2 + OH-1aq2. Suppose that a salt of HB+1aq2 is added to a solution of B1aq2 at equilibrium. (c) Will the pH of the solution increase, decrease, or stay the same?

472
views