A sealed beaker of what you are told is aqueous nickel sulfide was given to you by the local chemist and you put it on the window sill. After a few days, you notice that the mixture is getting thick toward the bottom. What is the nature of the initial nickel sulfide mixture, assuming that the temperature on the sill remained approximately constant? • View Available Hint(s) O It is a colloid. O It is a solution. It is a gas. It is a suspension.

I Review | Constants | Periodic Table Colligative properties are those that depend on the number of solute particles. Because electrolytes dissociate into ions, the concentration of particles in the solution is greater than the formula-unit concentration of the solution. For example, if 1 mol of Na2SO4 totally dissociates, 3 mol of ions are produced (2 mol of Na+ ions and 1 mol of SO4 ions). Thus, a colligative property such as osmotic pressure will be three times greater for a 1 mol L1 Na2SO4 solution than for a 1 mol L nonelectrolyte solution. Part A Assuming complete dissociation of the solute, how many grams of KNO3 must be added to 275 mL of water to produce a solution that freezes at – 14.5 °C? The freezing point for pure water is 0.0 °C and Kf is equal to 1.86 °C kg mol1. Express your answer to three significant figures and include the appropriate units. • View Available Hint(s) However, complete dissociation of electrolytes does not always occur. The extent of dissociation is…

14b

Lithium chloride has a solubility of 45.80 g in 100. g of water at 25°C. Express this solubility in terms ofmass percent molality mole fraction