Ch 12

Question 1

Homogeneous Mixtures (solutions)

Answer 1

The composition is uniform throughout

The different parts of the mixture are not visible

Question 2

Heterogeneous Mixtures

Answer 2

The composition of substances is not uniform

The composition varies from one part of the mixture to another

The different parts of the mixture are visible

Question 3

Solute

Answer 3

that which is dispersed in a solution (present in lesser amount)

Question 4

Solvent

Answer 4

dispersing agent (present in greatest amount)

Question 5

Solutes

Answer 5

Spread evenly throughout the solution.

Cannot be separated by filtration.

Can be separated by evaporation.

Are not visible, but can give a color to the solution.

Question 6

Two substances form a solution:

Answer 6

When there is an attraction between the particles of the solute and solvent.

When a polar solvent, such as water, dissolves polar solutes such as sugar and ionic solutes such as NaCl.

When a nonpolar solvent, such as hexane (C6H14), dissolves nonpolar solutes such as oil or grease.

Question 7

Solubility

Answer 7

The maximum amount of solute that will dissolve in a given amount of solvent under a particular set of conditions

Question 8

Unsaturated solutions

Answer 8

Contain less than the maximum amount of solute.

Can dissolve more solute.

Question 9

Saturated solutions

Answer 9

Contain the maximum amount of solute that can dissolve.

Have undissolved solute at the bottom of the container.

Question 10

Factors Affecting Solubility: Pressure

Answer 10

The solubility of gases in liquids increases with pressure

Question 11

Factors Affecting Solubility: Temperature

Answer 11

The solubility of gases in liquids DECREASES with temperature

In general, the solubility of solids in liquids increases with temperature

Question 12

Ionic compounds that dissolve in water are

Answer 12

soluble salts

Question 13

Ionic compounds that dissolve in water are

Answer 13

insoluble salts

Question 14

When solutions of salts are mixed

Answer 14

A solid forms if ions of an insoluble salt are present

Question 15

Equations for Forming Solids

Answer 15

A molecular equation shows the formulas of the
compounds

An ionic equation shows the ions of the compounds.

A net ionic equation shows only the ions that form a solid.

Question 16

Steps for making a solution

Answer 16

1. Weigh out the solute, put it in a volumetric flask.
2. Add some water, mix the solute and the solvent.
3. Add water to the line on the volumetric flask.

Question 17

Concentration

Answer 17

Designates the amount of solute dissolved in a given quantity of solution

Question 18

There are many ways of designating concentration.

Answer 18

Percent concentration:

• Percent by mass (m/m)
• Percent by volume (v/v)

Molarity = M

Question 19

Molarity

Answer 19

A Conversion Factor between the mass of solute and the volume of solution
Molarity = moles of solute/ volume of solution in liters

Question 20

Dilution

Answer 20

Adding solvent to an existing solution to decrease the solution’s concentration.

Question 21

In a chemical reaction

Answer 21

The volume and molarity of a solution are used to determine the moles of a reactant or product.

molarity ( mol /1L) x volume (L)= moles

If molarity (mol/L) and moles are given, the volume (L) can be determined
moles x 1 L /moles =volume (L)