Chapter 11 Test

Question 1

What is energy?

Answer 1

The capacity or ability for doing work

Question 2

What do all physical and chemical changes involve?

Answer 2

the absorption or emission of energy (energy changes)

Question 3

What is heat?

Answer 3

The energy transferred as a result as result of a temperature difference.

Question 4

What is the symbol for heat?

Answer 4

q

Question 5

How is heat energy transferred?

Answer 5

Heat (energy) is transferred from the system of higher energy/temp to the system with lower energy/temp.

Question 6

What is a Joule?

Answer 6

unit of energy and heat

Question 7

What is a calorie?

Answer 7

the amount of heat required to raise the temperature of 1 gram of pure water 1 oC.

Question 8

What is the ratio of Joules to calories?

Answer 8

1 cal=4.184 J

Question 9

What are symbols for calories and Joules?

Answer 9

J and cal

Question 10

What is a Calorie?

Answer 10

1000 calories = 1kcal, used in our foods

the amount of energy the human body can obtain by chemically breaking down food.

Question 11

What is the symbol for a Calorie?

Answer 11

C

Question 12

What are exothermic reactions with respect to heat and energy?

Answer 12

Energy is given off by a reaction, usually in the form of heat. These reactions are usually spontaneous and the products have less energy than the reactants because energy is given off by the system.

Question 13

What are endothermic reactions with respect to heat and energy?

Answer 13

Energy is absorbed in a reaction. The products of this reaction are of higher energy than the reactants.

Question 14

What is a catalyst?

Answer 14

speeds up a chemical reaction by lowering the Activation energy.

Question 15

What is an inhibitor?

Answer 15

slows down a chemical reaction by lowering the Activation energy.

Question 16

What are the two sides of a chemical reaction equation?

Answer 16

Reactants —– Products

Question 17

What is a Calorimeter?

Answer 17

instrument used to measure energy given off or absorbed during a physical or chemical change.

Question 18

What is the Law of Conservation of Energy?

Answer 18

All chemical and physical changes obey this. A law of science that states that energy cannot be created or destroyed, but only changed from one form into another or transferred from one object to another.

Question 19

What is specific heat?

Answer 19

The amount of heat energy needed to raise the temperature of 1 gram of substance, 1 oC.

Question 20

What is the symbol for specific heat?

Answer 20

Cp

Question 21

What kind of specific heat to metals have?

Answer 21

Low

Question 22

What is heat capacity?

Answer 22

the amount of heat/energy needed to raise the temperature of an object 1.0oC

Question 23

What is the Cp of ice?

Answer 23

2.11 J/g degrees C

Question 24

What is the Cp of liquid water?

Answer 24

4.184 J/g degrees C

Question 25

What is the Cp of water vapor?

Answer 25

2.08 J/g degrees C

Question 26

What is the specific heat equation?

Answer 26

Specific Heat (Cp) = Heat (J)/ Mass (g) x ΔT (oC)

Question 27

How to you rearrange the specific heat equation to solve for the heat needed?

Answer 27

q=(m)(Cp)(ΔT)

Question 28

What is enthalpy of fusion?

Answer 28

the energy required to melt a substance at its melting point

Question 29

What is enthalpy of solidification?

Answer 29

the energy released when a substance freezes at its freezing point

Question 30

What is enthalpy of vaporization?

Answer 30

the energy required to vaporize a substance at its boiling point

Question 31

What is enthalpy of condensation?

Answer 31

the energy released when a substance condenses

Question 32

What is the symbol for enthalpy of a change of matter state?

Answer 32

∆H

Question 33

What is boiling point?

Answer 33

the temperature at which the vapor pressure of the liquid is equal to the atmospheric pressure

Question 34

What is melting point?

Answer 34

the temperature at which the vapor pressure of the solid and liquid phases of a substance is equal

Question 35

What is freezing point?

Answer 35

the temperature when the vapor pressure of liquid equals the vapor pressure of the solid.

Question 36

In the water specific heat diagram, describe the change types they are based on heat and energy.

Answer 36

All of these changes are endothermic when they go up (melting, vaporization), but when they go opposite, it is exothermic (condensation, freezing)

Question 37

What is ∆Hfus for pure water?

Answer 37

334 J/g

Question 38

What is ∆Hvap for pure water?

Answer 38

2260 J/g

Question 39

What is ∆Hsolid for pure water?

Answer 39

-334 J/g

Question 40

What is ∆cont for pure water?

Answer 40

-2260 J/g