CHAPTER I

INTRODUCTION

1.1. Background

Thermodynamics (Greek: thermos = 'hot' and dynamic = 'change')

is the physics of energy, heat, work, entropy and the spontaneity of

processes. Thermodynamics closely related to statistical mechanics in

which many thermodynamic relations derived. On the system are in the

process exchange matter or energy, classical thermodynamics is not related

to the reaction kinetics (speed of the reaction process). Due to this reason,

the use of the term "thermodynamics" usually refers to equilibrium

thermodynamics. With this connection, the main concept in

thermodynamics is kuasistatik process, which is idealized, the process of

"super slow". Thermodynamic processes in the studied time-dependent

non-equilibrium thermodynamics.

Because thermodynamics is not concerned with the concept of

time, it has been proposed that it should be called a thermostatic

equilibrium thermodynamics. Law of thermodynamics truth is very

common, and these laws do not depend on the details of the interactions or

the systems being studied. This means they can be applied to a system in

which a person does not know anything but the balance of energy and

matter transfer between them and the environment. Examples include

estimates of the Einstein spontaneous emission in the 20th century and

current research on the thermodynamics of black objects.

Thermodynamic system is part of the universe that counts. A real

limitation or imagination separating system with the universe, which is

called the environment. Classification system based on the thermodynamic

properties of the system-surrounding boundary and flows of matter,

energy and entropy between the system and the surrounding.

1.2. Summary of Problems

Based on the background that was displayed, then there are some problems

to be used as a guide in compiling this paper.

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1.2.1. How is the general meaning of Thermodynamics?

1.2.2. How the system and the range of Thermodynamics?

1.2.3. How is the system (state of the system)?

1.2.4. How the meaning of Thermodynamics process?

1.2.5. How temperature and thermometer?

1.3. Purposes

Based on the formulation of the problem has been displayed, the purpose

of this paper is as follows.

1.3.1. Describes the general meaning of Thermodynamics.

1.3.2. Describes the system in Thermodynamics and surroundings.

1.3.3. Identified system state (state of the system).

1.3.4. Describes the process in thermodynamics.

1.3.5. Describes the temperature and thermometer.

1.4. Benefits

Benefits that can be obtained from the writing of this paper are as follows:

1.4.1. For Authors

Benefits for authors of this paper are the authors have extended

knowledge about the study of thermodynamics specialist for system

and surrounding including phenomena that exist in daily life and can

apply the basic concepts of system and surrounding.

1.4.2. For Readers

The benefits of writing this paper for the reader is able to understand

and be able to apply the concept of thermodynamics specialist for

system and surrounding.

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CHAPTER II

DISCUSSION

2.1. The General Definition of Thermodynamics

In a simple definition, thermodynamics refer to a branch of science

(physics) which deals to the matter consisted in equilibrium toward

temperature’s change, pressure, and chemical compositions. More specific,

Thermodynamics defined as a study of science deals either with the

relationship or the change between heat and work. This relation or change

based on empirical definition namely the first and the second law of

Thermodynamics (Rapi, 1999). Further defined Thermodynamics refer to

a study of relationships, involving heat, mechanical work, and other

aspects of energy and energy transfer (Young & Freedman, 2010). For

example, in a car engine heat is generated by chemical reaction of oxygen

and vaporized gasoline in the engine’s cylinders. The heated gas pushes on

the piston within the cylinder, doing mechanical work that is used to

propel the car.

The existence of thermodynamics provides principles and methods

which is further used to :

a. Explain the work of several systems.

b. Explain the condition why a system does not work as what expected.

c. Explain why a system does not work at all.

d. Become a theoretical based for the engineers in planning systems or

machines such as heat engine, thermal pump, rocket’s engine, electric

power plant, gas turbine, air conditioner, high power laser, solar

heating system, and other else.

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Figure 1. The use of thermodynamics

2.2. Thermodynamics’ System and Surroundings

Thermodynamics always deal with two major components namely

Thermodynamics system and surroundings. Thermodynamics system

defined as parameter that used to designate the working substance (the

thing that becomes the major focus) inside a closed boundary. These

closed boundaries can be imaginary or even real. While the Term

surroundings refer to the rest of the universe that interacts with the system

(All space in the universe outside the thermodynamic system).

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Figure 2. Simple analogies of thermodynamics’ system and

surroundings

To convenient the understanding of the systems here are given

some other analogies:

a) Compressed air inside a cylinder, in this case the air that being

compressed refers to a system, whiles the closed boundaries given by

the surface covered by the cylinder.

b) A 90 0C metal and 27 0C water inside a vessel, there will be a thermal

equilibrium on the both objects. In this case water and the metal are the

system meanwhile the boundaries covered by the vessel refers to the

closed real boundaries.

c) An ice chunk floats on a water, in this case the closed boundaries of

water refer to a closed which is tend to be imaginary since the water

has a very large area (Halliday & Resnick, 1998).

Regarding to whether there are mass or energy transfer take place,

systems can be further classified into three major points namely:

1) Open System

An open system can exchange both mass and energy with its

surroundings. Open systems have walls that allow transfer of both

energy and matter to and from the system.

2) Closed System

A closed system can exchange energy, but not mass, with its

surroundings. Closed systems have walls that allow transfer of energy

into or out of the system but are impervious to matter. They therefore

have a fixed mass and composition but variable energy levels.

3) Isolated System

An isolated system cannot exchange mass or energy with its

surroundings. Isolated systems have walls or boundaries that are rigid

(thus not permitting transfer of mechanical energy), perfectly

insulating (thus preventing the flow of heat), and impermeable to

matter. They therefore have a constant energy and mass content, since

none can pass in or out. Perfectly insulating walls and the systems they

enclose are called adiabatic. Isolated systems, of course, do not occur

in nature, because there are no such impermeable and rigid boundaries

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(Halliday & Resnick, 1998). Nevertheless, this type of system has

great significance because reactions that occur (or could occur) in

isolated systems are ones that cannot liberate or absorb heat or any

other kind of energy.

Figure 3. The Thermodynamics’ system (a) an open system, (b)

a closed systems, and (c) an isolated system

2.3. The System State (State of a System)

State of thermodynamic systems can be expressed by some

quantities, such as pressure (p), temperature (T), volume (V), and density

(ρ). State of thermodynamic systems can be expressed with the quantities

mentioned above and the relationship between these quantities is called

equation of state (Giancolli, 2001).

In the thermodynamic quantity divided into two massive extensive

quantity and intensive quantity. First, extensive quantity is a quantity that

is affected by the mass or number of moles of the system. For example:

volume, and heat capacity (C). Second, intensive quantity is a quantity that

is not influenced by the mass or number of moles of the system. For

example: pressure and temperature.

Thermodynamic coordinate system or state variable is the quantity

that can describe the state of the system. State of the system depends on

the coordinate system. This means the state will change if the coordinate

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a cb

system is changed (Giancolli, 2001). Examples of gas contained in the

cylinder, the system state is represented by the pressure, volume, and

temperature. In this case p, V, and T are called the coordinates of

thermodynamics or the system state variables. State of the system will

change if the pressure, volume, or change the gas temperature.

Figure 4. State of the system depends on the coordinate system

State of the new system can be regarded as the coordinates of the

system when the system is in thermodynamic equilibrium. When the

system is isolated, the system is not affected by the environment, but

changes may occur in the system, and these changes will stop after some

interval of time, and at this point the system is said to have reached

equilibrium conditions and are unlikely to change again (Masi, 2011).

System is in a state of thermodynamic equilibrium, when the

system is in a state of mechanical equilibrium, chemical equilibrium, and

thermal equilibrium as follows.

1. Mechanical Equilibrium

The system is in mechanical equilibrium, if the resultant force acting

on the part of the system or the system with the environment equal to

zero (the pressure in all parts of the same system).

2. Chemical Equilibrium

The system is in chemical equilibrium, if the system does not undergo

spontaneous changes of internal structure (such as chemical reactions,

diffusion, and dissolution).

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Gas

p, V, dan T

3. Thermal Equilibrium

The system is in thermal equilibrium, if the temperature of the system

together with the ambient temperature and the temperature of all parts

of the same system.

2.4. Definition of Process

When a closed system move from equilibrium or if coordinate of

thermodynamics is change, like pressure, volume, or temperature, we can

say that the system do a process, during that characteristics of system are

change until realize the new equilibrium state (Hamid, 2007). So, we can

say that any change that a system undergoes from one equilibrium state to

another is called a process, and the series of states through which a system

passes during a process is called the path of the process, like Figure 5. To

describe a process completely, one should specify the initial and final

states of the process, as well as the path it follows, and the interactions

with the surroundings.

The kind of interaction differed become three, those are interaction

through work outside, interaction through heat, interaction through work

outside and exchange heat. Every those situation have the characteristics

and apart calculations (Hamid, 2007). Hence, so important to know those

basics and definitions. The general fundamental like that:

1) Reversible Process

Reversible process is the process of changing from an initial state to

another state, and the final state is possible occurrence of reverse process

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Figure 5. Process Path

to the initial state of the easy when the system is subject to certain

conditions. A process is said to invert (reversible), as well as meet the

requirements, the process is the process quasistatik. While quasistatik

process is defined as a process that at every level of the system changes in

sequence often reach equilibrium states.

2) Irreversible Process

Irreversible process is the opposite of a reversible process, the process

is cannot be reversed from the final state toward initial state through the

same path. In general, naturally occurring process is irreversible process.

For example, heat flows from objects which have a higher temperature to

the object that has a lower temperature. It may not be reversed naturally.

3) Adiabatic Process

Adiabatic process is a process that is not accompanied by the exchange

of heat between the system with the environment, in this case the system is

isolated from the environment, the system interaction with the

environment occurs only through great effort. In this process applies

dQ=0. This situation can occur if the system is well insulated, or the

process happens so quickly that heat (which flows with slow) does not

have time to flow into or out. Rapid gas expansion on the combustion

engine is almost adiabatic process. Slow adiabatic expansion of an ideal

gas follows the curves as follows.

Figure 6. Adiabatic Process

4) Isotherm Process

Isotherm process is the process in a system where the temperature is

constant, dT=0 and in this process of Boyle's law applies Marriotte PV=C.

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If the system is an ideal gas PV=nRT. This process follows the curve of

the PV diagram below.

Figure 7. Isotherm Process

5) Isocorik Process

Isocorik process is a process in which the system is constant volume,

dV=0 and in this process applies the formula P/T=C. This process follows

the curve of PV as in the following diagram:

Figure 8. Isocorik Process

6) Isobar Process

Isobar process is a systematic process that pressure is constant, dP =0

and in this process applies formula V/T=C. This process follows the curve

of PV as AB in the following diagram:

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Figure 9. Isobar Process

2.5. Temperature and Thermometer

Between system and environment are dividing walls, and between

the system with other systems are also the dividing wall. The dividing wall

can be adiabatic and diatermik. If the separation wall is adiabatic then

there will be no thermal interaction (heat exchange) between systems with

other systems (isolated system). Thermal interactions will occur if the

separation wall is diatermal and between systems with different

environmental are temperatures (Satriawan, 2003).

So the temperature is a quantity that is jointly owned two or more

systems in a state of thermal equilibrium. Some say the temperature is a

measure of heat-chill of an object. Hot-cold an object is related to the

thermal energy contained in the object. The greater the thermal energy, the

greater the temperature.

Size serves to indicate the temperature of the heat energy in a solid,

liquid, or gas. The method usually use one of the changes in properties of a

material due to heat, such as expansion, and electrical properties

(Satriawan, 2003).

2.5.1.Thermal Contact

Two things to saying a state of thermal contact when the thermal

energy can be exchanged between two objects without any work done

(Zemansky & Richard, 1986). For example, of two system is systems A

and B before the interaction/contact stated, the system A pressure P1 and

temperature T1 and system B is expressed by the pressure P2 and

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temperature T2. Between systems A and B bounded by walls that are

diatermik. After the interaction state of the system A is expressed by the

pressure P1' and temperature T1'. And system B is expressed by the

pressure P2' and the temperature T2'. As in the show in the chart below.

Thermal contact coordinates on each system change, but a new

equilibrium state is achieved after heat moves from warmer system to a

system that is less hot. In this new equilibrium both systems have the same

magnitude, namely temperature T1=T2, such as the thermal contact

between water and ice. Ice has a lower temperature than water, so ice will

receive the heat from the water in the event of thermal contact to a

situation where the water temperature and ice is same.

2.5.2. Thermal Equilibrium

The thermal equilibrium is situation where two objects are in

contact thermal exchange of thermal energy in the same amount. The time

required to reach thermal equilibrium depends on the nature of the object.

At the time of thermal equilibrium to the two objects have the same

temperature.

2.5.3. The Zero of Thermodynamics Law

To-zero law of thermodynamics is an emphasis on the concept of

temperature. For more details, will be assessed through this chart.

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AP1, T1 P2, T2 P1’, T1’ P2’, T2’

diatermikB A B

Before After

Figure 10. Different state of things which had thermal contact with the no thermal contact

We examine three system A, B, and C, respectively stated

condition: P1, V1, T1; P2, V2, T2; P3, V3, T3. When a system is in thermal

equilibrium with system B, then T1=T2 and system A is also in a state of

thermal equilibrium with system C, then system C is also in a state of

thermal equilibrium with system B. The temperature of a system would be

similar to the temperature system B and with temperature system C or

T1=T2=T3.

The Zero of thermodynamics law is read “If objects A and B

respectively in thermal equilibrium with third object C, then objects A and

B in a state of thermal equilibrium with each other”. C is the third thing

which we will later call thermometer. Two objects A and B are in thermal

equilibrium have the same temperature. In the SI system of units

temperature is Kelvin (K) without a degree. The scale of temperature

measurement in degrees Celsius is equal to the Kelvin scale measure, but

the same zero point oC 273,15K. oC zero point is the condition of the ice

meltsat standard atmospheric conditions, while the condition of 0K is

absolute zero where all the conditions that produce energy movement in

all material stops.

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B

P2

V2

T2

P3

V3

T3

C

P1

V1

T1

A

Figure 11. Three systems the situation is different

2.5.4. Thermometer

Thermometer is an instrument used to measure temperature or

changes in temperature. The term thermometer comes from the Latin

“thermo” means “heat”, and “meter” which means “to measure”

(Zemansky & Richard, 1986). Affixed thermometer need a scale to be

used for the quantitative measurement of temperature. All types and kinds

thermometers based on the symptoms that a certain physical quantities

change when the temperature is changed or modified. Such physical

quantities is named Thermometric Property. The types of thermometers

based on Symptoms which certain physical quantities change when the

temperature changes, among others: the gas thermometer pressure fixed,

fixed volume gas thermometer, liquid thermometer, thermometer resistor

and thermistor thermometers. Thermometers explanations include:

2.5.4.1.Thermometer Gas on Constant Pressure

On this type of thermometer, gas volume on the thermometer will

change due to changes in temperature and can be expressed by the

equation V=V(T).

Figure 12. Thermometer Gas on Constant Pressure

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Figure 13.Thermometer Gas in Constant Volume

2.5.4.2.Thermometer Gas in Constant Volume

Thermometer is

almost perfect/ideal is a

constant-volume gas

thermometer. The working

principle of constant-volume

gas thermometer is as

follows. Gas volume be kept

fixed. When the temperature

increases, the gas pressure

also increases. In pipe 1and

pipe 2 contained mercury.

Gas volume be kept constant,

by raising or lowering the

pipe 2 so that the surface of the mercury in the tube 1 has always been the

reference marks. If the temperature or the temperature increases, the gas

pressure in the tube will also increase. Therefore, the pipe should be

removed 2 higher order volume of gas is always constant.

Gas pressure can be known by reading the mercury column height

(h) in the pipe 2. If you use the manual method, just remember the

column of mercury as high as 760 mm = 1 atm pressure (1 atmosphere).

Usually the volume gas thermometer is equipped with a counter pressure.

Receptacles containing gash as also been designed so that gas is always

in a fixed volume. So the pressure is measured only changes alone

(Zemansky & Richard, 1986).

2.5.4.3.Fluid Thermometers

On this type of thermometer length of fluid in the thermometer will

change due to changes in temperature and can be expressed by the

equation L = L (T). Working principle of liquid thermometers use the

basic principles of expansion in the liquid. Liquid level rise indicates

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expansion, the greater the heat received, the greater the increase in the

level of liquid. Liquid commonly used as mercury and alcohol. For

example Fahrenheit thermometer, Celsius, Reamur (Masi, 2011).

2.5.4.4. Resistor Thermometers

On this type of thermometer, ρ (density resistor material)

changes due to changes in temperature and can be expressed by the

equation ρ=ρ(T). The thermometer usually use a fine platinum wire is

wound pad of mica and thin silver tube inserted in a heat-resistant. On the

thermometer resistance, usually measured changes in electrical resistance

of a coil of wire or thin cylinders of carbon or germanium crystal. Because

the electrical resistance can usually be measured precisely, then the

resistance thermometer can measure temperature more accurately than

regular thermometer (Masi, 2011).

Figure 15. Thermometer Resistor

2.5.4.5. Bimetallic Thermometer

This thermometer has two pieces of metal that have different

expansion coefficients. When there is a change in the temperature of the

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Figure 14. Fluids Thermometer

metal, the two pieces will be curved in one direction. If the temperature is

high, then the puck will be curved in the direction of metal its expansion

smaller coefficient (Rapi, 1999). Meanwhile, when the temperature is low,

the two pieces will curve to the metal its expansion coefficient greater.

Figure 16 . Bimetallic Thermometer

2.5.4.6. Infrared Thermometer

This thermometer measures the temperature using the radiation

emitted by a black box object (Rapi, 1999). Sometimes called laser

thermometers if a laser to help work measurement, or no touch

thermometer to illustrate the tool's ability to measure temperature from a

distance. By knowing the amount of infrared energy emitted by the object

and its emissions, the temperature of the object can be distinguished.

2.5.4.7. Galileo Thermometer

This thermometer is made of mercury that are placed in a glass

tube. Calibrated marks on the tube which makes the temperature can be

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Figure 17. Infrared Thermometer

read within the length of the mercury in the glass varies according to

temperature.

Figure 18 . Galileo Thermometer

2.5.4.8. Thermistor

Thermistor is a device or component or electronic sensors used to

measure temperature. The basic principle of the thermistor is a resistance

value changes (or barriers or werstan or resistance) if the temperature or

the temperature of the thermistor is changed.

Figure 19. Thermistor

Of the few examples of thermometers above, suppose the

thermometer gas at a constant pressure, the liquid thermometer, and

thermometer barriers, large values of V, L, and is mentioned by

thermometric property is a physical properties change as the temperature

changes. In facilitating reading thermometer scale, thermometric property

is always chosen as a linear function of temperature (T).

If thermometric property denoted by x can be formulated x = x (T),

for x chosen as a linear function of T then the next can be formulated as

follows (Rapi, 1999).

x=C.T or .......................... Equation 1

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So that from the equation, the calculation can be written as:

    or .......................... Equation 2

Specification:

T1 = temperature to be measured

x1 = Thermometric property values on the temperature to be measured

T2 = reference temperature

x2 = thermometric property value at a reference temperature

Furthermore, the international system of units (SI) has been agreed

that as the temperature of the triple point of reference taken pure water

with a value of T2 = 273,160K, so that equation (2) will be

.......................... Equation 3

As for the gas thermometer at a fixed volume, the equation can be written:

   or ............. Equation 4

And if the amount of gas used in the thermometer is low, then

thermometer gas at constant volume related thermometer between linear

and T really met properly, as in the following equation:

.............. Equation 5

However, based on the experiments it is known that the type of gas

does not affect the measurement. Therefore thermometer called a fixed

volume of an ideal gas thermometer and 5 above equation is the definition

of an ideal gas temperature. Triple temperature is the temperature at which

pure water is in a state of thermal balance with ice and saturated vapor

value T=273,160K Ice point is the temperature at which ice and water are

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in thermal equilibrium at a pressure of 1 atm (Rapi, 1999). Ice point value

= 00C= 273,150K.

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CHAPTER III

CLOSING

3.1. Conclusions

Based on the discussion above, some conclusions can be take as follows:

3.1.1. Thermodynamics is a study of Physics deals with the relation of

energy, energy transfer, chemical composition of substance, and

mechanical work.

3.1.2. Thermodynamics deals with two major components namely system

and surroundings which is separated by closed boundaries that can

be real or imaginary. Thermodynamics system can be further

defined regarding to there are mass transfer or energy transfer, into

three classes namely open system, closed system, and isolated

system.State of thermodynamic systems can be stated with some

quantities, such as pressure (p), temperature (T), volume (V), and

density (ρ).

3.1.3. State of thermodynamic systems can be stated with some

quantities, such as pressure (p), temperature (T), volume (V), and

density (ρ).

3.1.4. The system do the process if system change from the equilibrium

state to another state.

3.1.5. Temperature is a quantity that is jointly owned two or more

systems in a state of thermal equilibrium. The greater the thermal

energy, the greater the temperature. Thermometer is an instrument

used to measure temperature or changes in temperature. Affixed

thermometer need a scale to be used for the quantitative

measurement of temperature.

3.2. Suggestion

As for suggestions that can authors give to the reader so that the reader

understand the material in thermodynamic specific for system and

surroundings, so that readers can add insight and can apply it in daily life.

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Giancoli, D. C. 2001. Fisika Edisi Kelima Jilid 1. Jakarta :Erlangga.

Halliday & Resnick. 1999. FISIKA Jilid 2. Jakarta: Erlangga.

Hamid, A. A. 2007. “Diktat Termodinamika”. Dalam http://staff.uny.ac.id/sites/default/files/Diktat%20Termodinamika.pdf. Diakses pada tanggal 5 September 2014.

Masi, M. 2011. “Thermodynamics System and State Fuctions”. Dalam http://www.eolss.net/sample-chapters/c06/e6-11-04-01.pdf. Diakses pada tanggal 5 September.

Rapi, N. K. 1999. Buku Ajar Termodinamika. Singaraja :Jurusan Pendidikan Fisika FMIPA UNDIKSHA.

Satriawan, M. 2003. “Termodinamika”. Dalam http://mirza.staff.ugm.ac.id/termo/TERMODINAMIKA.pdf. Di akses pada tanggal 5 September 2014.

Young, H.D. & Freedman, R.A. 2010. University Physics. United States: Adison Wesley.

Zemansky, M. & Richard H. 1986. Kalor dan Termodinamika Terbitan Keenam. Bandung : ITB.

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