Chemhw5.6

A solution that is at equilibrium must be saturated. At equilibrium, the rate of dissolution of solute particles is equal to the rate of precipitation, resulting in a balance between dissolved and undissolved particles. A saturated solution contains the maximum amount of solute that can be dissolved at a given temperature, meaning that any additional solute will not dissolve and will remain undissolved. Therefore, a saturated solution is at equilibrium because there is no net change in the concentration of the solute.

NaCl(aq) is a homogeneous mixture because it is a solution where NaCl is dissolved in water. In a homogeneous mixture, the components are evenly distributed at a molecular level, resulting in a uniform composition throughout the mixture. NaCl(aq) meets this criteria as the NaCl particles are dispersed and surrounded by water molecules, forming a single phase with no visible separation. In contrast, NaCl(s) is a solid, NaCl(l) is a liquid, and NaCl(g) is a gas, all of which are not homogeneous mixtures as they consist of only one phase and do not have components evenly distributed.

A dilute, aqueous potassium nitrate solution is best classified as a homogeneous mixture because it consists of a single phase in which the potassium nitrate is evenly distributed throughout the water. In other words, the composition and properties of the solution are uniform throughout, making it a homogeneous mixture.

not-available-via-ai

NaNO3 is the correct answer because it is a salt that can dissolve in water to form an unsaturated solution at 40C. The fact that 80 grams of the salt is dissolved in 100 grams of water indicates that the solution is unsaturated, as a saturated solution would require the maximum amount of salt to be dissolved in the given amount of water. Therefore, NaNO3 is the salt that can form an unsaturated solution in this scenario.

According to Reference Table G, a saturated solution is a solution that contains the maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature. In this case, the question states that the solution contains 50 grams of solute per 100 grams of water at 75°C. Therefore, the correct answer is a saturated solution of KCl, as it is the only option that matches the given concentration of solute in the solvent.

According to Reference Table G, NaNO3 forms an unsaturated solution when 80 grams of the substance is added in 100 grams of H2O at 10C. This means that NaNO3 has the ability to dissolve in water at this temperature and concentration, without reaching its maximum solubility.

According to Reference Table G, a solution is considered saturated when it contains the maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature. In this case, the solution contains 120 grams of NaNO3 dissolved in 100 grams of H2O, which is more than the maximum amount of solute that can dissolve in that amount of solvent at 50C. Therefore, the solution is supersaturated. Additionally, since the solution contains a large amount of solute (120 grams) in a relatively small amount of solvent (100 grams), it is considered concentrated.

The solution in the flask is saturated and at equilibrium with the solid KCl because no more solid KCl dissolves when the flask is thoroughly shaken. This indicates that the solution has reached its maximum solubility, and the amount of dissolved KCl is in equilibrium with the amount of undissolved solid KCl.

NH3 (ammonia) is most soluble in H2O (water) at STP (standard temperature and pressure) because it can form strong hydrogen bonds with water molecules. Ammonia molecules have a lone pair of electrons that can attract the positively charged hydrogen atoms in water, forming hydrogen bonds. These hydrogen bonds increase the solubility of NH3 in water. On the other hand, KCl, HCl, and NaNO3 do not form strong hydrogen bonds with water, resulting in lower solubility compared to NH3.