Карточки Thermodynamic Processes | Quizlet

Isobaric

No change in pressure; Q = ΔU + W; W = nRΔT; W = PΔV

(Charles Law)

Isochoric

No change in volume; W = 0; Q = ΔU

(Gay-Lussac's Law)

Isothermal

No change in temperature; W = Q;

(Boyle's Law)

Adiabatic

No heat added or removed; No change in entropy; ΔU = -W; ΔS = 0

Entropy

The measure of disorder in a system; ΔS = ΔQ/T; Increases with Volume and Temperature

Isothermal Compression

Gives off heat without changing internal temperature.

Isothermal Expansion

Takes in heat without changing internal temperature.

Isobaric Expansion

Work is positive and is found using pΔV or nRΔT.

Isobaric Compression

Work is negative and is found using pΔV or nRΔT.

Isochoric Expansion

Work is zero, Heat is positive, and Temperature increases.

Isochoric Compression

Work is zero, Heat is negative, and Temperature decreases.

Adiabatic Expansion

No change in heat; Temperature increases, while work(volume) decreases.

Adiabatic Compression

No change in heat; Temperature decreases, while work(volume) increases.

Work

A change in volume. Cannot occur without a change in volume. Can be found by finding the area under a Pressure-Volume graph.

The First Law of Thermodynamics

Q = W + ΔU; Heat is equal to work plus change in internal temperature.

The Second Law of Thermodynamics

For any cycle of energy, some heat must be lost.

Work of a Heat Engine

Q(hot) - Q(cool) = Work; Q(hot) = Q(cool) + W

Efficiency

The amount of heat that is converted to Work;

e = W/Q(hot); e = 1- Q(cool)/Q(hot)

The Carnot Cycle

Theoretical cycle for the most efficient process of turning a given amount of heat into work.

Efficiency of the Carnot Cycle

e(c) = 1 - T(cool)/T(hot); Temperature is in Kelvin.

Isothermal Expansion

The first step of the Carnot Cycle. Constant hot temperature, takes in heat.

Adiabatic Expansion

The second step of the Carnot Cycle. T(hot) becomes T(cool) with no change in heat.

Isothermal Compression

The third step of the Carnot Cycle. Constant cold temperature, Heat leaves the engine.

Adiabatic Compression

The last step of the Carnot Cycle. T(cool) becomes T(hot) with no change in heat.

Temperature

The measure of average kinetic energy. Also indicates the direction of heat flow.

Internal Energy

What heat becomes when absorbed by a gas.