Problem 35 - Chemistry The Central Science

Question

Indicate whether each statement is true or false: (a) The higher the temperature, the more soluble most gases are in water. (b) The higher the temperature, the more soluble most ionic solids are in water. (c) As you cool a saturated solution from high temperature to low temperature, solids start to crystallize out of solution if you achieve a supersaturated solution. (d) If you take a saturated solution and raise its temperature, you can (usually) add more solute and make the solution even more concentrated.

Step-by-Step Solution

Answer

(a) False: The solubility of most gases decreases with increasing temperature. (b) True: The solubility of most ionic solids increases with increasing temperature. (c) True: Solids start to crystallize out of a supersaturated solution when cooled. (d) True (usually): Raising the temperature of a saturated solution typically allows more solute to dissolve, making the solution more concentrated.

Step 1: Statement A: The higher the temperature, the more soluble most gases are in water.

This statement is false. The solubility of most gases in water decreases as the temperature increases. This is because gas molecules have more kinetic energy and escape the solution more easily at higher temperatures.

Step 2: Statement B: The higher the temperature, the more soluble most ionic solids are in water.

This statement is generally true. The solubility of most ionic solids in water increases as the temperature increases. With higher temperature, the kinetic energy of water molecules increases, which helps to break the ionic bonds in the solid and dissolve the ions in the water.

Step 3: Statement C: As you cool a saturated solution from high temperature to low temperature, solids start to crystallize out of solution if you achieve a supersaturated solution.

This statement is true. A supersaturated solution is unstable and contains more solute than it can hold at its current temperature. When a supersaturated solution is cooled to a lower temperature, the solubility of the solute decreases, and the excess solute will start to crystallize out of the solution to return to equilibrium.

Step 4: Statement D: If you take a saturated solution and raise its temperature, you can (usually) add more solute and make the solution even more concentrated.

This statement is generally true. Raising the temperature of a saturated solution typically increases the solubility of the solute in the solution. This means that at higher temperatures, more solute can be dissolved, making the solution more concentrated. However, this might not be true for all solutes, as some may exhibit different behaviors under specific conditions.