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Flashcards in Basic concepts Deck (27)
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1
Q

What is a Rigid Boundary?

A

Prevents a system from changing shape or size

2
Q

What does Adiabatic mean?

A

Prevents a system from changing unless the boundary is changed

3
Q

What is an Isolating System?

A

Both adiabatic and rigid

4
Q

What is a Diathermal system?

A

Permits flow-through of heat

5
Q

What is a permeable system?

A

Permits passage of matter, otherwise impermeable

6
Q

What is a closed system?

A

Mass cannot cross the boundaries but energy can

7
Q

What are the 3 types of property of a system?

A

Intensive Extensive Specific

8
Q

Intensive property

A

System size independent

Cannot be added up

Examples: Temperature and Pressure

9
Q

Extensive property

A

System size dependent

Can be added up

Examples: Volume and mass

10
Q

Specific property

A

Extensive properties/unit mass

11
Q

Specific Volume

A

Volume/unit mass

The inverse of density V=v/m=1/density

12
Q

Specific Gravity

A

The ratio of the density of a substance to the density of some standard substance (usually water at 4 degrees C)

13
Q

What is a State?

A

At a given state all values for the properties are known, changing one property changes the state

14
Q

What is Equilibrium ?

A

A system is said to be in equilibrium if it maintains thermal, mechanical, phase (the mass of the phases) and chemical equilibrium

15
Q

What is the State Postulate?

A

The thermodynamic state of a simple compressible system is completely specified by 2 independent intensive properties

16
Q

What is a Quasi-equilibrium or quasi-static process?

A

A process where the system remains practically in equilibrium at all times

17
Q

Isobaric

A

Constant Pressure

18
Q

Isothermal

A

Constant Temperature

19
Q

Isochoric

A

Constant Volume

20
Q

Isoentropic

A

Constant Entropy

21
Q

What is a cycle?

A

A process (or series of connected processes) with identical end states

22
Q

Carnot Cycle

A
  1. Isothermal Expansion
  2. Adiabatic Expansion
  3. Isothermal Compression
  4. Adiabatic Compression
23
Q

Diesel Cycle

A
  1. Intake
  2. Compression
  3. Power
  4. Exhaust
24
Q

What is Heat?

A

The energy transfer that appears at the boundary when a system changes its state due to a difference in temp. between the system and its surroundings

25
Q

What is Work?

A

The energy transfer that appears at the boundary when a system changes its state due to movement of a part or the whole of the boundary under the action of a force

26
Q

What is the ice point?

A

A mixture of ice and water that is in equilibrium with air saturated with vapour of 1 ATM. Pressure

27
Q

What is the steam point?

A

A mixture of liquid water and vapour (with no air) in equilibrium at 1 ATM. pressure