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what is the standard unit of energy in the SI ?

Is the Joule (J). One joule = One kg.m2/s2

calculate the amount of work that can be extracted from a thermal energy reservoir with constant temperature. (geef formule)

W= Qh - Ql

W=the amount of work delivered

Qh=the heat extracted from the high temperature reservoir

Ql= the heat added to the low temperature reservoir

So the total entropy change of the process will be:

delta S = Qh/T - Ql /Tref

the second law says that the total of entropy changes in such a closed system is larger than or equal to zero. Now, let us first assume that we have an ideal process, where the entropy does not increase: delta S = 0.

For ideal processes the following formula can be used:

W= (1-Tref/T) x Qh

we can conclude that for this ideal process, the maximum amount of work produced is always smaller than the heat extracted from the reservoir, which brings us back to our first formulation of the second law of thermodynamics.

W=the amount of work delivered

Qh=the heat extracted from the high temperature reservoir

Ql= the heat added to the low temperature reservoir

So the total entropy change of the process will be:

delta S = Qh/T - Ql /Tref

the second law says that the total of entropy changes in such a closed system is larger than or equal to zero. Now, let us first assume that we have an ideal process, where the entropy does not increase: delta S = 0.

For ideal processes the following formula can be used:

W= (1-Tref/T) x Qh

we can conclude that for this ideal process, the maximum amount of work produced is always smaller than the heat extracted from the reservoir, which brings us back to our first formulation of the second law of thermodynamics.

describe the entropy concept (geef de formule)

delta S = delta Q / T

delta S = entropy change

delta Q= heat extraction

T = Temperature

delta S = entropy change

delta Q= heat extraction

T = Temperature

Describe the second law of thermodynamics?

In simple words: "heat cannot be fully converted into work"

The relation between internal energy E and enthalphy H is as follows:(geef de formule)

H= E + p x V

H=enthalphy

E=internal energy (also often indicated with the letter U)

p=pressure

V=Volume

for solids and liquids, the difference between H and E is very small, but for gases the difference cannot generally be neglected

H=enthalphy

E=internal energy (also often indicated with the letter U)

p=pressure

V=Volume

for solids and liquids, the difference between H and E is very small, but for gases the difference cannot generally be neglected

the change in enthalphy is measured by.......

adding (or removing) energy under constant pressure

the change in internal energy of a substance is measured by ......

adding (or removing) energy under constant volume

In practice, two slightly different concepts of energy content are used. which ones ?

-(internal) energy

-enthalphy

-enthalphy

in energy analysis, we generally use an environmental reference system, with the reference state for each chemical element the most stable naturally-occurring compound of that element. give some examples

carbon = CO2

water = H20

water = H20

The energy content is dependent on conditions like.. (give some examples)

-pressure and temperature, and is always determined in comparison to a reference state.