Chapter 1: Intro Concepts and Definitions

Question 1

System

Answer 1

The object of study; The composition of the matter in the system may be fixed or may change through chemical or nuclear reactions. The shape or volume doesn’t have to be constant.

Question 2

Surroundings

Answer 2

Everything external to the system.

Question 3

Boundary

Answer 3

The separation between a system and its surroundings.

Question 4

Closed Systems (Control Mass)

Answer 4

Fixed quantity of matter within a system. There is no transfer of mass across its boundary.

Question 5

Control Volume (Open System)

Answer 5

Is a region of space (boundary) through which mass may flow in and out.

Question 6

Control Surface (Boundary)

Answer 6

When the term control mass and control volume are used, the system boundary is often referred to as a control surface.

Question 7

Isolated System

Answer 7

a closed system that doesn’t interact with its surroundings in any way.

Question 8

Choosing a system boundary take into consideration…

Answer 8

• what is known about possible system, particularly at boundaries.
• objective for analysis.

Question 9

property

Answer 9

is a macroscopic character of a system such as mass, volume, energy, pressure and temperature to which a numerical value can be assigned at a given time without knowledge of the previous behavior.

Question 10

State

Answer 10

Condition of a system as described by its properties.

Question 11

Process

Answer 11

a transformation from one state to another.

Question 12

Steady State

Answer 12

when the properties of a system don’t change over time.

Question 13

Extensive Properties

Answer 13

properties that depend on the size/ extent of the system. Functions of only time. Ex: Mass, Volume, Energy.

Question 14

Intensive Properties

Answer 14

properties that are independent of the size or extent of a system at any moment. Are functions of bot position and time. Ex: Specific Volume, Temperature

Question 15

Determining what is a Property

Answer 15

A quantity is a property if, and only if , its change in value between two states id independent of the process. ( only depends on end states not process path)

Question 16

Equilibrium

Answer 16

In mechanics, equilibrium means a condition of balance maintained by an equality
of opposing forces. In thermodynamics, the concept is more far-reaching, including
not only a balance of forces but also a balance of other influences.

Question 17

Equilibrium State

Answer 17

Isolate the system from its surroundings and
watch for changes in its observable properties.If there are no changes, we conclude
that the system was in equilibrium at the moment it was isolated.

Question 18

Specific Volume

Answer 18

The specific volume y is defined as the reciprocal of the density. It is the volume per unit mass. Like density, specific volume is an intensive property
and may vary from point to point.

Question 19

Zeroth Law of Termodynamics

Answer 19

It is a matter of experience that when two objects are in thermal equilibrium with a third object, they are in thermal equilibrium with one another.

Ex: It is necessary only to see if they are individually in thermal equilibrium with a third object. The third object is usually a thermometer .