Q: If the molar solubility of $$PbBr_2 is$$ $$1.0 \times 10$$^{-2}$$ mol/L, what is the value of K$$_{sp}$$ for $$PbBr_2$$?

$$K_{sp} = 4.0 \times 10$$^{-6}$$

Question 1

Which of the following statements best describes a saturated solution?

Accepted Answer

A solution in which there is more solid present than can be dissolved, and both solid and dissolved solute are in equilibrium.

Question 2

Which of the following compounds is predicted to be insoluble in water based on general solubility rules?

Accepted Answer

Ag2S

Question 3

Given the solubility product equilibrium for $$BaS(s) \rightarrow Ba$$^{2+}$$(aq) + S$$^{2-}$$(aq)$$, which expression correctly represents the $$K_{sp}$$?

Accepted Answer

$$K_{sp} = [Ba$$^{2+}$$] [S$$^{2-}$$]$$

Question 4

If the molar solubility of $$PbBr_2 is$$ $$1.0 	imes 10$$^{-2}$$ mol/L, what is the value of K$$_{sp}$$ for $$PbBr_2$$?

Accepted Answer

$$K_{sp} = 4.0 	imes 10$$^{-6}$$

Question 5

Which of the following best explains the common ion effect?

Accepted Answer

Adding a common ion decreases the solubility of a salt by shifting the equilibrium toward the solid.

Question 6

For the dissociation of $$Ca_3$$($$PO_4)_2(s$$) \rightarrow $$3Ca^{2+}(aq) + 2PO$$_$$4^{3-}(aq$$)$$, if the molar solubility is s$, what is the correct K$$_{sp}$$ expression in terms of s$?

Accepted Answer

$$K_{sp} = (3s)^3$ (2s)^2$

Question 7

A student adds HCl to a solution containing AgCl. What will happen to the solubility of AgCl and why?

Accepted Answer

The solubility of AgCl will decrease because the added Cl- shifts the equilibrium toward the solid.

Question 8

Which of the following is true about the solubility product constant $$K_{sp}$$?

Accepted Answer

$$K_{sp} is $$the equilibrium constant for the dissolution of a solid in water.

Question 9

Which of the following best describes a buffer solution?

Accepted Answer

A solution that resists changes in pH when small amounts of acid or base are added.

Question 10

The Henderson-Hasselbalch equation is used in buffer calculations. Which is the correct form of the equation?

Accepted Answer

$$pH = pK_a + \log \left( \frac{[A^-]}{[HA]} \right)$$

Question 11

A buffer is most effective when:

Accepted Answer

The concentrations of acid and conjugate base are equal.

Question 12

Which of the following titration curves would show a buffer region?

Accepted Answer

Titration of a weak acid with a strong base.

Question 13

If the $$K_{sp} of$$ $$Ag_2CO_3 is$$ $$8.1 	imes 10$$^{-12}$$, what is the molar solubility of Ag_2CO_3$?

Accepted Answer

$$1.3 	imes 10$$^{-5}$$ mol/L

Question 14

Which of the following is NOT a step in calculating the molar solubility from $$K_{sp}$$?

Accepted Answer

Assume the concentration of ions is always 1 M.

Question 15

Which principle explains why adding $$Cl^- to a $$solution containing $$AgCl$$ causes more $$AgCl to $$precipitate?

Accepted Answer

Le Châtelier's Principle

Question 16

A solution contains $$0.45 M$$ $$KBr. If$$ $$CuBr(s) is $$added, what effect does the $$Br^-$$ concentration have on the molar solubility of $$CuBr$$?

Accepted Answer

It decreases the molar solubility due to the common ion effect.

Question 17

Which of the following is true about the buffer range?

Accepted Answer

It is the pH range over which the buffer can effectively resist changes in pH.

Question 18

Which of the following is the correct dissociation reaction for $$Mg(OH)_2 in $$water?

Accepted Answer

$$Mg(OH)_2(s) \rightarrow Mg$$^{2+}$$(aq) + 2OH^-(aq)$$

Question 19

Which of the following is a correct approach to finding $$K_{sp}$$ from molar solubility?

Accepted Answer

Write the solubility product reaction, use the molar solubility to find equilibrium concentrations, and substitute into the $$K_{sp}$$ expression.

Solubility, Solubility Product, and Common Ion Effect: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard