CH6-7

Question 1

What is a solution?

Answer 1

A homogeneous mixture of two or more substances

Solutions consist of at least one solute and one solvent.

Question 2

Define solute.

Answer 2

The component of a solution that is present in lesser quantity

Examples include salt in saltwater.

Question 3

Define solvent.

Answer 3

The solution component present in the largest quantity

Water is the most common solvent.

Question 4

What is an aqueous solution?

Answer 4

A solution where the solvent is water

Question 5

What are electrolytes?

Answer 5

Formed from solutes that are soluble ionic compounds

Question 6

What is solubility?

Answer 6

How much of a particular solute can dissolve in a certain solvent at a specified temperature

Question 7

What factors affect solubility?

Answer 7

• Polarity of solute and solvent
• Temperature
• Pressure

The more different the polarities, the lower the solubility.

Question 8

What is a saturated solution?

Answer 8

A solution that contains all the solute that can be dissolved at a particular temperature

Question 9

What is a supersaturated solution?

Answer 9

Contains more solute than can be dissolved at the current temperature

Question 10

What occurs at equilibrium in a saturated solution?

Answer 10

The rates of dissolution and precipitation are equal

Question 11

Define concentration.

Answer 11

Amount of solute dissolved in a given amount of solution

Question 12

How do you calculate mass/volume percent?

Answer 12

Mass/Volume Percent = (mass of solute in grams / volume of solution in milliliters) × 100

Question 13

What is molarity?

Answer 13

The number of moles of solute per liter of solution

Question 14

What are colligative properties?

Answer 14

Properties of solutions that depend on the concentration of solute particles, rather than the identity of the solute

Question 15

What is Raoult’s law?

Answer 15

When a nonvolatile solute is added to a solvent, vapor pressure of the solvent decreases in proportion to the concentration of the solute

Question 16

What is boiling point elevation?

Answer 16

The increase in boiling temperature necessary to raise the vapor pressure to atmospheric pressure when a solute is present

Question 17

Define freezing point depression.

Answer 17

The interference of solute molecules with the rate at which liquid water molecules associate to form the solid state

Question 18

What is osmotic pressure?

Answer 18

The amount of pressure required to stop the flow across a semipermeable membrane

Question 19

Define isotonic solutions.

Answer 19

Solutions with identical osmotic pressures and no osmotic pressure difference across the cell membrane

Question 20

What defines a hypertonic solution?

Answer 20

Solute concentration of fluid surrounding cells is higher than inside, causing water to flow out and cell collapse

Question 21

What defines a hypotonic solution?

Answer 21

Solute concentration of fluid surrounding cells is lower, causing water to flow into the cell and rupture it

Question 22

What is an exothermic reaction?

Answer 22

A reaction that releases energy to the surroundings

Question 23

What is an endothermic reaction?

Answer 23

A reaction that absorbs energy from the surroundings

Question 24

Define enthalpy.

Answer 24

Energy content released during bond formation or required to break chemical bonds

Question 25

What does ΔH represent?

Answer 25

The energy difference between the products and reactants of a chemical reaction

Question 26

What is entropy?

Answer 26

The measure of the statistical distribution of energy in a system

Question 27

What does ΔG indicate?

Answer 27

Determines if a reaction will occur and predicts reaction spontaneity

Question 28

What is calorimetry?

Answer 28

The experimental measurement of heat energy changes in a chemical reaction

Question 29

Define activation energy (Ea).

Answer 29

The minimum amount of energy required to initiate a chemical reaction

Question 30

What factors influence reaction rate?

Answer 30

* Structure of reactants * Temperature * Concentration * Presence of a catalyst ## Footnote More collisions lead to faster reactions.

Question 31

What is a dynamic equilibrium?

Answer 31

A situation where the rate of the forward process in a reversible reaction is balanced by the rate of the reverse process

Question 32

What does LeChatelier’s Principle state?

Answer 32

If a stress is placed on a system at equilibrium, the system will respond to minimize that stress

Question 33

What effect does increased temperature have on an exothermic reaction?

Answer 33

Shifts equilibrium left, favoring the reactants

Question 34

What effect does increased temperature have on an endothermic reaction?

Answer 34

Shifts equilibrium right, favoring the products

Question 35

What is the effect of pressure on equilibrium?

Answer 35

Only significantly affects gases; increases equilibrium towards fewer gas molecules