Unit 7: Solutions & Solubility
9) Define the term, unsaturated solution.
A solution that has less solute dissolved than the maximum amount possible.
11) Define the term, supersaturated solution?
A solution that has more solute dissolve that should be physically possible.
7) Define the term, saturated solution.
A solution that has the maximum amount of solute dissolved as is physically possible. Equilibrium
23) What are the 4 formulas used to measure "concentration"?
Percent Composition, Molarity, Molality, and Mole Fraction
32) What are colligative properties?
Properties of solutions that depend upon the ratio of the number of solute particles to the number of solvent molecules in a solution, and not on the type of chemical species present.
15) What is the ONE factor that will affect the solubility of solid solutes in liquid solvents?
Temperature
34) Explain what is meant by the term, freezing point depression.
Adding a solute to a solvent decreases the freezing point of the solvent.
8) What happens to extra solute added to a saturated solution?
Any extra solute added will NOT dissolve; it just sinks to the bottom.
14) Define the term, precipitate.
Cause (a substance ) to be deposited in solid form from a solution.
4) Describe the term, like dissolves like.
Chemicals with the same polarity will dissolve into one another.
22) What does it mean if a solution is considered to be concentrated? Dilute?
Concentrated: a lot of solute relative to the amount of water. Dilute: only a small amount of solute relative to the amount of water.
10) What happens to extra solute added to an unsaturated solution?
Extra solute added will dissolve into the solution.
17) What are the TWO factors that will affect the solubility of gaseous solutes in liquid solvents?
Temperature and Pressure
18) What happens to the solubility of gases as the temperature increases?
Th solubility decreases as the temperature increases.
16) What happens to the solubility of solids as temperature increases?
The solubility increases as the temperature increases.
28) What is the % composition by mass formula?
% composition by mass= mass of part/ mass of whole x 100
30) What is the % composition by volume formula?
% composition by volume= volume of solute/ volume of solution x 100
5) Explain how to determine solubility.
1. Look up the salt's cation and anion separately 2. If either ion is on the Soluble list, the salt will dissolve in water (unless the exception is true!) 3. If either ion is on the Insoluble list, the salt won't dissolve in water (unless the exception is true!)
31) Give an example of a % composition by volume question and solve it.
25.0 mL ethanol/ 100.0 mL solution x 100 = 25.0 vol %
1) Define the term, solution.
A homogenous mixture where one substance dissolve in a secong substance.
33) Explain what is meant by the term, boiling point elevation.
A non-volatile solute is added to a pure solvent.
12) What happens to extra solute added to a supersaturated solution?
If you add extra solute, all of the EXTRA dissolved solute will precipitate, leaving a saturated solution. Only the excess solute precipitates.
25) Give an example of a molarity question on the front; solve it on the back.
M= 5g/ 20L M=.25g/L
24) What is the molarity formula?
Molarity= moles of solute/ volume of solution in liters
21) What does it mean if you have a solution, at a certain temperature, which has more grams dissolved than the line on a solubility curve? less? Exactly the same?
More grams: Supersaturated Less grams: Unsaturated Same: Saturated
20) What do the graphed lines represent?
Solubility curves
19) What happens to the solubility of gases as pressure increases?
Solubility of the gases increases
3) Define the terms, soluble and insoluble.
Soluble: If a solute does dissolve. Insoluble: If a solute does not dissolve.
2) Define the terms, solute and solvent.
Solute: The chemical being dissolved. Solvent: The chemical doing the dissolving.
6) What is referred to as the "universal solvent"?
Water (H2O)
13) How do you make a supersaturated solution?
You must saturate the solution fully by adding to solute to the solvent until no more dissolves.