State whether each of the following refers to a saturated or an unsaturated solution:
a. A crystal added to a solution does not change in size.

Potassium nitrate has a solubility of 32 g of KNO₃ in 100. g of H₂O at 20 °C. Determine if each of the following forms an unsaturated or saturated solution at 20 °C:

a. adding 32 g of KNO₃ to 200. g of H₂O

In general, as the temperature increases, the solubility of gas in a given liquid ________________, and the solubility of most solids in a given liquid ________________. 

a. Increases, increases

b. increases, decreases

c. decreases, increases

d. decreases, decreases

A solution is prepared by dissolving 12.5 g of KBr in 20 mL of water at 60 °C (see Figure 9.3). Is this solution saturated, unsaturated, or supersaturated? What will happen if the solution is cooled to 10 °C?

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State whether each of the following refers to a saturated or an unsaturated solution:

c. A uric acid concentration of 4.6 mg/100 mL in the kidney does not cause gout.

Explain the following observations:

a. More sugar dissolves in hot tea than in iced tea.

Use the following graph for problems 1.55 and 1.56:

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d. Does the solubility of carbon dioxide increase or decrease with an increase in temperature?

If all the solute is dissolved in diagram 1, how would heating or cooling the solution cause each of the following changes?

a. 2 to 3

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Potassium nitrate has a solubility of 32 g of KNO₃ in 100. g of H₂O at 20 °C. Determine if each of the following forms an unsaturated or saturated solution at 20 °C:

a. adding 32 g of KNO₃ to 200. g of H₂O