Lesson 3

Question 1

All chemical reactions exhibits the two
fundamental laws:

Answer 1

the law of conservation of
mass
the law of conservation of energy.

Question 2

It is defined as the capacity to do
work.

Answer 2

Energy

Question 3

________, unlike matter, cannot be seen,
touched, smelled, or weighed but all of its
form are capable of doing work.

Answer 3

Energy

Question 4

directed energy change resulting from
a process.

Answer 4

work

Question 5

There are different forms of energy namely:

Answer 5

Kinetic energy

Thermal energy

Chemical energy, and

Potential energy

Question 6

All forms of energy can be ________ from one form
to another, but can neither be _______ nor ___________.

Answer 6

transformed
created
destroyed

Question 7

In this law, the total quantity of
energy in the universe is assumed constant.

Answer 7

law of conservation of energy

Question 8

it is the transfer of thermal energy between two bodies
that are at different temperatures

Answer 8

heat

Question 10

is the study of heat change in chemical
reactions.

Answer 10

thermochemistry

Question 10

is the specific part of the universe that is of interest to us

Answer 10

system

Question 11

are the rest of the universe outside the
system.

Answer 11

surroundings

Question 11

Three types of system:

Answer 11

(a) Open, (b) Closed and (c) Isolated system.

Question 12

system where it can exchange mass and
energy, usually in the form of heat with its
surroundings.

Answer 12

open system

Question 13

what system
Example. Boiling soup in an open saucepan
on a stove.

Answer 13

open system

Question 14

A system that allows the transfer of
energy (heat) but not mass.

Answer 14

closed system

Question 15

what system?
Example. A pressure cooker on a stove with
its lid tightly closed and the whistle in position

Answer 15

closed system

Question 16

A system that does not allow the
transfer of either mass or energy.

Answer 16

isolated systm

Question 17

what system
Example. A thermos flask containing hot
water

Answer 17

isolated

Question 18

Any energy lost from the system, or the
given reacting mixture, is gained by the
surroundings.

Answer 18

exothermic process

Question 19

any process
that gives off heat. example: combustion reaction

Answer 19

exothermic

Question 20

heat has to be
supplied to the system by the
surroundings.

Answer 20

endothermic process

Question 21

It is the measurement of heat changes.

Answer 21

calorimetry

Question 22

It is a closed container designed specifically to
measure heat changes.

Answer 22

calorimeter

Question 23

The ____________ of a substance is the amount of heat required to raise the temperature of one gram of the substance by one degree Celsius (J/g·°C).

Answer 23

specific heat (s)

Question 24

specific heat formula

Answer 24

s=q/(mΔT)

Question 25

The _____ of a substance is the amount of heat required to raise the temperature of a given quantity of the substance by one degree Celsius (J/°C.).

Answer 25

Heat Capacity (C)

Question 26

Specific heat is an _________ property whereas heat capacity is an _________ property.

Answer 26

intensive extensive

Question 27

The relationship between the heat capacity and specific heat of a substance is ______,where m is the mass of the substance in grams.

Answer 27

C = ms

Question 28

heat change formula

Answer 28

q = CΔt or q = msΔt

Question 29

+q is for __________ process and -q is for ___________ process.

Answer 29

endothermic exothermic

Question 30

Heat of combustion is usually measured by placing a known mass of a compound in a steel container called a _________________, which is filled with oxygen at about 30 atm of pressure.

Answer 30

constant-volume bomb calorimeter

Question 31

is used to determine the heat changes for non-combustion reactions. They used it in measuring the heat effects of a variety of reactions such as acid-base neutralization as well as Heat of solution and heat of dilution.

Answer 31

constant-pressure bomb calorimeter

Question 32

is a thermodynamic quantity equivalent to the total heat content of a system.

Answer 32

enthalpy

Question 33

It is equal to the internal energy of the system plus the product of pressure and volume.

Answer 33

enthalpy

Question 34

The work is done on the surroundings for an expansion process and it is done on the system for a compression process.

Answer 34

enthalpy

Question 35

shows the enthalpy change as well as the mass relationships. It is essential to specify a balanced equation when quoting the enthalpy change of a reaction.

Answer 35

thermochemical equations

Question 36

deals with the interconversion of heat and other forms of energy.

Answer 36

Thermodynamics

Question 37

If a reaction does occur under the given set of conditions is called _________.

Answer 37

spontaneous reaction

Question 38

If a reaction does not occur under the given set of conditions is called _________.

Answer 38

nonspontaneous

Question 39

To determine the spontaneity of the reaction, a thermodynamic quantity called ________ must be considered.

Answer 39

entropy

Question 40

__________is described as a measure of how spread out or dispersed the energy of a system is among the different possible ways that system can contain energy.

Answer 40

Entropy (S)

Question 41

is the absolute entropy of a substance at 1 atm and 25°C.

Answer 41

standard entropy

Question 42

The units of entropy are ______________for 1 mole of the substance.

Answer 42

J/K or J/K·mol

Question 43

The ____ states that energy can be converted from one form to another, but it cannot be created or destroyed.

Answer 43

First Law of Thermodynamics

Question 44

The ___________ is defined as the entropy of the universe increases in a spontaneous process and remains unchanged in an equilibrium process.

Answer 44

Second Law of Thermodynamics

Question 45

The second law of thermodynamics tells us that a spontaneous reaction increases the entropy of the universe; that is, ___________

Answer 45

ΔSuniv > 0

Question 46

In order to express the spontaneity of a reaction more directly, we introduce another thermodynamic function called __________

Answer 46

Gibbs free energy (G), or simply free energy

Question 47

The___________is the free-energy change for a reaction when it occurs under standard-state conditions.

Answer 47

standard free-energy of reaction (ΔGo)

Question 48

The ________________ states that entropy of a perfect crystalline substance is zero at the absolute zero of temperature.

Answer 48

Third Law of thermodynamics