Chapter 16 Key Concepts

Question 0

What units are usually used to express the solubility of a solute?

Answer 0

Grams of solute per 100g of solvent

Question 1

What determines whether a substance will dissolve? What determines how fast a substance will dissolve?

Answer 1

The compositions of the solvent and the solute; stirring (agitation), temperature, and surface area

Question 2

What are two conditions that determine the mass of solute that will dissolve in a given mass of solvent?

Answer 2

Temperature and pressure

Question 3

How do you calculate the molarity of a solution?

Answer 3

Divide the moles of solute by the volume of the solution (in liters)

Question 4

Compare the number of moles of solute before dilution with the number of moles of solute after dilution.

Answer 4

Diluting a solution reduces the number of moles of the solute per unit volume, but the total number of moles of solute in solution does not change.
Moles of solute= M1xV1=M2xV2

Question 5

What are two ways of expressing the concentration of a solution as a percent?

Answer 5

The ratio of the volume of the solute to the volume of the solution or the ratio of the mass of the solute to the mass of the solution

Question 6

What are the three colligative properties of solutions?

Answer 6

Vapor-pressure lowering, boiling-point elevation, and freezing-point depression

Question 7

What factor determines how much the vapor pressure, freezing point, and boiling point of a solution differ from those properties of the pure solvent?

Answer 7

The number of solute particles dissolved in the solvent

Question 8

What are two ways of expressing the ratio of solute particles to solvent particles?

Answer 8

Unit molality and mole fractions

Question 9

How are freezing point depression and boiling point elevation related to molality?

Answer 9

They are directly proportional to the molal concentration when the solute is molecular, not ionic