13.1.1 Types of Solutions Flashcards
Types of Solutions
- A solution is formed by the dissolution of a solute in a solvent.
- Solutions can be unsaturated, saturated, or supersaturated.
- Like dissolves like. Polar solvents tend to dissolve ionic and polar compounds, and nonpolar solvents tend to dissolve nonpolar compounds.
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- A solution is formed by the dissolution of a solute in a solvent.
- The final concentration of solute in a saturated solution depends only on the properties of the solvent and the temperature, not the amount of solute present.
- Solutions can be unsaturated, saturated, or supersaturated.
- An unsaturated solution is one in which the solute readily dissolves, while a saturated solution cannot dissolve any additional solute. A supersaturated solution contains a solute at concentrations higher than its solubility.
- As more of the solute is added to a solution, the concentration in solution rises linearly. The saturation point is reached when the concentration of a solute no longer increases with the addition of more solute. The concentration of a solute at the saturation point is referred to as the solute’s solubility in the solvent. As more solute is added, the dissolved solute and undissolved solute reach a dynamic equilibrium, where the solute undergoes balanced exchanges between dissolved and undissolved forms.
- The solubility of a solute in a solvent is influenced by their respective molecular structures. Compounds with high solubilities have relatively weak bonds, while compounds with strong bonds, such as sand or diamond, will be virtually insoluble. Ionic compounds are the exception—while they have strong bonds, polar solvents such as water, which stabilize the ions in solution, can easily dissolve them. \
- A good rule of thumb is “like dissolves like”. Polar solutes are most soluble in polar solvents such as water, alcohols, and ketones. Nonpolar solutes are most soluble in nonpolar solvents such as ethers, halocarbons, and hydrocarbons
Look at the graph that compares the moles of solute (added to a solution) to the concentration of the solute in the solution.
Assume that you are starting at Point 1 with a pure solvent. You then slowly add solute particles until you reach Point 5. Which statement best describes what is happening at each point (1 − 5) in the process?
At Point 0, the graph shows that you have a pure solvent (i.e., no solute). From Point 0 to Point 3, solute is added and dissolved. Beyond Point 3, none of the additional solute that is added is dissolved because the solution is saturated.
Table salt is added to water in table spoon amounts. It is stirred into solution until solid salt remains on the container bottom and does not dissolve. Which statement about this demonstration is not true?
The concentration of dissolved salt increased continually as more salt was added.
The diagram compares the moles of solute added to a solution to the concentration of the solute in the solution. The concentration of the solute in the solution is the amount of solute dissolved in the solution.
Each of the five points is associated with one of the following terms: an unsaturated solution, a saturated solution with excess undissolved solute, a supersaturated solution, the saturation point, or the solubility for the solution. Which of the following matches each term with its correct number on the graph?
Point 1: solubility; Point 2: an unsaturated solution; Point 3: the saturation point; Point 4: a saturated solution with excess undissolved solute; Point 5: a supersaturated solution
What is a saturated solution?
A saturated solution is a solution that contains the maximum possible concentration of solute (at a given temperature).
Look at the diagram that compares the moles of solute added to a solution to the concentration of the solute in the solution.
Three of the four answer choices below use the same value for the concentration of solute in solution. For which number point on the graph is the solute in solution different from the other three points in the choices below?
Point 2
Which of the following statements best summarizes the solubility of solutes in solvents?
Like dissolves like. (In other words, solutes that have similar bonding schemes to their solvents will be more soluble than solutes that have bonding arrangements different from their solvents.)
Which of the following best describes Point 5 on the graph?
At this point, the solution is supersaturated. It has more dissolved solute (at a given temperature) than would normally be expected
Suppose that you do the following simple demonstration for saturation of a solution.
Step 1: Place 1 teaspoon of salt into the solution and stir. Observation: All of the salt dissolves.
Step 2: Place 1 teaspoon of salt into the solution and stir. Observation: All of the salt dissolves.
Step 3: Place 1 teaspoon of salt into the solution and stir. Observation: Some of the salt dissolves.
Step 4: Place 1 teaspoon of salt into the solution and stir. Observation: None of the salt dissolves.
Step 5: Place 1 teaspoon of salt into the solution and stir. Observation:?
Which statement about this demonstration is not true?
By adding the salt more slowly to the saturated solution, you can increase the concentration of dissolved salt.
Suppose that you do the following simple demonstration for saturation of a solution.
Step 1: Place 1 teaspoon of salt into the solution and stir. Observation: All of the salt dissolves.
Step 2: Place 1 teaspoon of salt into the solution and stir. Observation: All of the salt dissolves.
Step 3: Place 1 teaspoon of salt into the solution and stir. Observation: Some of the salt dissolves.
Step 4: Place 1 teaspoon of salt into the solution and stir. Observation: None of the salt dissolves.
Step 5: Place 1 teaspoon of salt into the solution and stir. Observation:?
Which statement best explains what happened and also predicts what will be observed in Step 5?
Salt was added to a solution in increments of 1 teaspoon each time. During Steps 1 and 2, the solution remained unsaturated. During Step 3, the solution reached its saturation point. Any salt added after Step 3 would not dissolve, including the salt from Step 5.
Which of the following statements about a saturated solution is not true?
In a saturated solution, the solute atoms and molecules no longer change states (between dissolved and undissolved solute) because equilibrium exists.
