1. Describe the system, surroundings, types of
systems and intensive and extensive properties for
the thermodynamic systems.
System
The universe = The system + The surroundings
 In thermodynamics, a system is a specific portion of the universe that is being studied
and analyzed.
 It can be any region or volume of space that is separated from its surroundings by a
boundary, which can be real or imaginary.
 A thermodynamic system refers to that part of the universe in which observations are
made, and the remaining universe constitutes the surroundings.
 The system can be composed of a single substance or multiple substances, and it can be
in any state of matter (solid, liquid, gas, or plasma).
 The system can interact with its surroundings through various forms of energy transfer,
such as heat and work through a boundary.
Surroundings
 The surroundings are everything outside of the system with which it can potentially
interact.
 Can apply to the environment, other thermodynamic systems, or anything in touch with
the system.
 Depending on the type of system and the nature of the contact, the environment may
exchange energy, matter, or both with the system.
 Can affect the behavior and properties of the system by changes in temp or pressure
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Boundary

The boundary between the system and surroundings can be
open, closed, or isolated, depending on the type of system
being studied.
Example:
 In a car, the engine burns gasoline inside the
cylinder and is considered as a
thermodynamic system
 The radiator, piston, exhaust system and air
outside form the environment of the system.
 The inner surfaces of the cylinder and piston
are considered as the boundary.
Types of Thermodynamic Systems:
Thermodynamic systems are classified as :
1. Open systems
2. Closed systems
3. Isolated Systems
1. Open systems: These are systems that can
exchange both matter and energy with their
surroundings. For example, an engine that
takes in fuel and expels exhaust gases is an
open system. Another example: A steam turbine
2. Closed systems: A system which has the ability to exchange only energy with its
surroundings and cannot exchange matter is known as a closed system. For example, a
sealed container of gas is a closed system.
3. Isolated systems: These are systems that cannot exchange either matter or energy with
their surroundings.
 For example, the universe as a whole can be considered an isolated system. Another
Example: Reactants are present in a thermos flask or an insulated vessel, where neither
energy nor matter is exchanged with the environment.
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Intensive and extensive properties for the thermodynamic
systems.
1. Intensive properties: are properties of a system that do not depend on the size or
amount of the system.
 Examples of intensive properties include temperature, pressure,specific heat capacity
and density.
 These properties are often used to describe the state of a system.For example, the
temperature and pressure of a gas are intensive properties that can be used to describe
the state of the gas regardless of the volume of the container it is in.
2. Extensive properties: are properties of a system that depend on the size or amount of
the system, meaning that they can be added together for different parts of a system to
obtain the total value for the entire system.
 Examples of extensive properties include mass, volume, and energy.
 These properties can be used to describe the overall size or amount of a system.for
example: The energy of a substance is proportional to its mass and its internal energy,
and therefore, the total energy of a system is the sum of the energies of all its
constituent parts.
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